docs(form-builder): WS-5b partial sign-off — SCHEMA v2.3 + ARCH v1.5 §17.4 + addendum Q3

dev-docs/ARCH-CONSOLIDATION-ADDENDUM-2026-04-24.md

@@ -156,6 +156,26 @@ class FormField extends Model
 
 **Git-log kanttekening commit 3.** De 1Password signer gaf herhaalde "failed to fill whole buffer" errors op de lange HEREDOC body van de bedoelde commit-message; de uiteindelijke commit landde met alleen de titel (`refactor(form-builder): pre-publish check reads form_field_bindings; drop binding JSON columns`, SHA `61719bf`). De volledige rationale — pre-publish check switch van JSON naar relationele query, kolom-drops op `form_fields.binding` en `form_field_library.default_binding`, factory/resource/form-request cleanup, fixture-rewrites — staat in de WS-5a completion notitie, niet in `git show 61719bf`. Amenden is niet geprobeerd: CLAUDE.md verbiedt signed-commit amenden.
 
+### Uitvoering — WS-5b (2026-04-25)
+
+WS-5b splitst `form_fields.validation_rules` en `form_field_library.validation_rules` naar een relationele tabel `form_field_validation_rules`. Rij-shape: `owner_type` / `owner_id` (polymorphic morph, hergebruik van de WS-5a aliassen) + `rule_type` string(40, app-enforced enum `FormFieldValidationRuleType`) + `parameters` JSON per rule-type. Rationale: rule_type is de queryable dimensie ("welke velden hanteren regex?"), waarden zijn heterogeen (int voor min_length, string voor regex, array voor mime_types) waardoor JSON *per rij* passend is, niet voor de hele bag.
+
+**Seed-scan resultaat (Phase A).** Zes distinct top-level keys geobserveerd in seeders/factories/tests/resource-code-paden: `min`, `max`, `regex`, `unique`, `max_priorities`, `tag_categories`. `required` bestond niet in de wild (kolom `is_required` was al de bron van waarheid). Enum-catalogus uitbreiding beperkt tot de vijftien validatie-cases; non-validatie-keys verplaatsen naar een parallelle tabel.
+
+**Strict-enterprise scope-uitbreiding.** Tijdens de decision gate is WS-5b uitgebreid met een parallelle tabel `form_field_configs` (zie ARCH §17.5, landed in WS-5b commit 5). Rationale: `tag_categories` en `storage_disk` zijn renderings-/upload-configuratie, geen validatie-regels. Ze opnemen in `form_field_validation_rules` zou de tabel-naam semantisch vervuilen — precies het type drift dat deze sprint opruimt. Eén extra tabel, één extra enum, één extra service, één extra scope; géén scope-creep verder dan dat paar.
+
+**Key-translaties bij backfill.**
+- `required`, `unique`: WARN-log + skip. Kolom-duplicaten van `is_required` / `is_unique`. In WS-5b commit 3 is de `FormValueService::$rules['unique']` fallback verwijderd — `is_unique` is nu de enige bron.
+- `max_priorities` → `rule_type = max_selected`: semantisch gelijk (cap op entries in list-valued veld); twee enum-cases voor één semantiek = rot. Seeder (`FormBuilderDevSeeder`) en test-assertie (`PublicFormSeederTest:190`) aangepast om de canonieke naam te gebruiken. Geen bridging in `toJsonShape`; historische snapshots blijven onaangeraakt.
+- Ambigu `min` / `max`: field-type dispatch — NUMBER → `min_value`/`max_value`; TEXT/TEXTAREA/EMAIL/PHONE/URL → `min_length`/`max_length`; DATE/DATETIME → `date_min`/`date_max`; anders **FAIL** migratie. Type-inappropriate gebruik van `min`/`max` is seed-data-bug; force correction, absorbeer niet stilletjes.
+- `tag_categories`, `storage_disk`: skipped door de validation-rules backfill met INFO log; commit 5's configs-backfill pickt ze op in `form_field_configs`.
+
+**Activity log-conventie.** Per §6.7 WS-5a: `field.validation_rules_replaced` wordt alleen geëmit op FormField-subject, niet op FormFieldLibrary. Library-niveau audits leven elders; bewuste convergentie met de binding-pattern.
+
+**Scope-sibling.** `FormFieldValidationRuleScope` is een near-duplicaat van `FormFieldBindingScope` (zelfde UNION-over-two-owner-chains shape). Base-class extractie is uitgesteld tot WS-5d (waar het derde sibling `form_field_options` een gedeelde vorm moet onthullen); premature abstractie uit twee is nog steeds premature. Cascade-observer `FormFieldBindingsCascadeObserver` is hernoemd naar `FormFieldChildTablesCascadeObserver` en ruimt nu drie child-tabellen op (bindings, validation-rules, en — vanaf commit 5 — configs).
+
+**Strict validator op save (commit 3).** De vier FormRequests (`StoreFormFieldRequest`, `UpdateFormFieldRequest`, `StoreFormFieldLibraryRequest`, `UpdateFormFieldLibraryRequest`) accepteren `validation_rules` nu als array-of-spec-objects (`[{rule_type, parameters, error_message_key?}, ...]`). Semantische validatie (enum-case + parameter-shape + callback-registry) loopt via `FormFieldValidationRuleService::assertSpecsValid()` in een `after()` hook, zodat bad specs 422 geven vóór enige write. Controllers schrijven niet langer `validation_rules` naar de JSON-kolom; writes gaan uitsluitend via `replaceRules()`.
+
 ---
 
 ## Q4 — Sanctum `personal_access_tokens`

dev-docs/ARCH-FORM-BUILDER.md

@@ -1,18 +1,21 @@
-# ARCH — Universal Form Builder (v1.4)
+# ARCH — Universal Form Builder (v1.5)
 
 > **Source of truth** for Crewli's universal Form Builder architecture.
 > Any discrepancy with SCHEMA.md is resolved in favour of this document
 > during the refactor. SCHEMA.md is updated at the end of the refactor.
 >
-> **Status:** Approved — WS-5a landed (relational `form_field_bindings`)
-> **Version:** 1.4 (§6.3 retitled to "Binding row specification"; new
-> §6.7 "Relational binding table"; §17.3 pre-publish check in present
-> tense per WS-5a)
-> **Previous version:** 1.3 (§10.4 public submission lifecycle —
-> draft/save/submit split with error envelope and drift detection),
+> **Status:** Approved — WS-5a landed (relational `form_field_bindings`);
+> WS-5b validation rules landed (relational `form_field_validation_rules`).
+> **Version:** 1.5 (§17.4 restructured into relational sub-sections:
+> catalogue, relational table, callback rules, legacy JSON migration).
+> **Previous versions:**
+> 1.4 (§6.3 retitled to "Binding row specification"; new §6.7 "Relational
+>   binding table"; §17.3 pre-publish check in present tense per WS-5a),
+> 1.3 (§10.4 public submission lifecycle — draft/save/submit split with
+>   error envelope and drift detection),
 > 1.2.1 April 2026 (§31.10 FORM-02 contract),
 > 1.2 April 2026 (per-purpose lifecycles, integration contracts, user
-> guidance principles, documentation coverage, in-app copy catalogue)
+>   guidance principles, documentation coverage, in-app copy catalogue).
 > **Created:** April 2026
 > **Owner:** Architecture doc; every session reads this before starting
 >
@@ -2206,16 +2209,150 @@ and diffs them against `requiredBindings`. External contract
    (identity-match, tag sync, entity creation, etc.).
 5. Add a lifecycle paragraph under §3.2 and a row to the table above.
 
-### 17.4 Custom validation callbacks
+### 17.4 Validation rules
 
-`form_fields.validation_rules` JSON supports callback references:
-```json
-{
-  "callback": "App\\Services\\Validators\\KvkValidator@validate"
-}
+Pre-WS-5b, validation rules lived as a flat JSON bag on
+`form_fields.validation_rules` and `form_field_library.validation_rules`.
+WS-5b moved them to the relational `form_field_validation_rules` table
+(one row per rule), in parallel with §6.7 (bindings). This section is the
+canonical home for the rule catalogue, the relational-table shape, the
+callback-registry integration, and the legacy-key migration notes.
+
+#### 17.4.1 Rule-type catalogue
+
+`FormFieldValidationRuleType` (PHP backed enum) is the canonical list of
+rule_type values. Each case documents the required `parameters` shape
+that `FormFieldValidationRuleService::replaceRules()` enforces.
+
+| `rule_type`          | `parameters` shape             | Notes                                                   |
+| -------------------- | ------------------------------ | ------------------------------------------------------- |
+| `min_length`         | `{"value": int}`               | Minimum character length for string-valued fields       |
+| `max_length`         | `{"value": int}`               | Maximum character length                                |
+| `min_value`          | `{"value": number}`            | Minimum numeric value for NUMBER fields                 |
+| `max_value`          | `{"value": number}`            | Maximum numeric value                                   |
+| `regex`              | `{"pattern": string, "flags": string?}` | `preg_match` pattern; flags optional            |
+| `email_format`       | `{}`                           | Boolean marker — enforces RFC-5321 email shape          |
+| `url_format`         | `{}`                           | Boolean marker — enforces URL shape                     |
+| `phone_e164`         | `{}`                           | Boolean marker — enforces E.164 phone shape             |
+| `allowed_mime_types` | `{"mime_types": [string]}`     | Whitelist for FILE_UPLOAD / IMAGE_UPLOAD / SIGNATURE    |
+| `max_file_size`      | `{"bytes": int}`               | Upper bound for uploads                                 |
+| `min_selected`       | `{"value": int}`               | Lower bound for multi-value selections                  |
+| `max_selected`       | `{"value": int}`               | Upper bound; covers the legacy `max_priorities` key     |
+| `date_min`           | `{"date": string}`             | ISO-8601 date; lower bound for DATE / DATETIME          |
+| `date_max`           | `{"date": string}`             | Upper bound                                             |
+| `callback`           | `{"key": string}`              | Registered callback key, see §17.4.3                    |
+
+**Not in the catalogue (deliberate):**
+
+- `required` — `form_fields.is_required` column is the single source of
+  truth. Any legacy `validation_rules.required` JSON is WARN-logged and
+  skipped at backfill.
+- `unique` — `form_fields.is_unique` column is the single source of
+  truth. The pre-WS-5b JSON fallback path in `FormValueService` was
+  stripped in WS-5b commit 3.
+- `tag_categories`, `storage_disk` — not validation rules, they are
+  field-rendering / upload-storage configuration. WS-5b relocates these
+  to a separate `form_field_configs` table (ARCH §17.5, landed in
+  WS-5b commit 5) rather than polluting the validation-rules catalogue.
+
+**Rule types are app-enforced, not DB enum.** The column is
+`string(40)` so the enum can extend in application code without a
+migration — identical rationale to `form_fields.field_type` (§4.2) and
+`CustomFieldTypeRegistry`.
+
+#### 17.4.2 Relational table `form_field_validation_rules`
+
+**Columns** (SCHEMA.md §3.5.12):
+
+| Column              | Type              | Notes                                                      |
+| ------------------- | ----------------- | ---------------------------------------------------------- |
+| `id`                | ULID              | PK                                                         |
+| `owner_type`        | string(40)        | morph alias: `form_field` or `form_field_library`          |
+| `owner_id`          | ULID              | parent row                                                 |
+| `rule_type`         | string(40)        | enum case value                                            |
+| `parameters`        | JSON              | per-rule-type bag                                          |
+| `error_message_key` | string(100) null  | optional i18n key for custom rejection copy                |
+| `created_at`, `updated_at` | timestamps |                                                            |
+
+- **Unique:** `(owner_type, owner_id, rule_type)` — at most one rule of
+  each type per field.
+- **Indexes:** `(rule_type)` for "which fields enforce regex?" queries,
+  `(owner_type, owner_id)` for per-owner lookups.
+- **Morph-map aliases** `form_field` and `form_field_library` are reused
+  from WS-5a (`AppServiceProvider::registerMorphMap`) — no new entries
+  needed.
+
+**Multi-tenancy (`FormFieldValidationRuleScope`).** Sibling to
+`FormFieldBindingScope` with identical UNION-over-two-owner-chains
+shape:
+
+```
+owner_id ∈ (
+  SELECT id FROM form_fields
+    WHERE form_schema_id ∈ (SELECT id FROM form_schemas WHERE organisation_id = ?)
+  UNION
+  SELECT id FROM form_field_library
+    WHERE organisation_id = ?
+)
 ```
 
-Registered callbacks in `config/form_builder.php`:
+Organisation context resolution mirrors `OrganisationScope`; the escape
+hatch is
+`FormFieldValidationRule::withoutGlobalScope(FormFieldValidationRuleScope::class)`.
+
+Base-class extraction between the two scope classes is deliberately
+deferred to WS-5d per addendum Q3 — premature abstraction from two
+siblings is still premature, and WS-5d's `form_field_options` /
+WS-5c's `form_field_conditional_logic` may surface a different shared
+shape.
+
+**Service boundary (`FormFieldValidationRuleService`).** All writes go
+through the service — no controller writes rules directly on the
+model. The service owns:
+
+- `rulesFor(owner)` — eager, scope-aware fetch.
+- `replaceRules(owner, specs)` — transactional delete + insert;
+  validates every spec's `rule_type` against the enum and `parameters`
+  against the per-rule shape (including callback-key registry check).
+  Logs `field.validation_rules_replaced` on the owning FormField
+  subject (matching the WS-5a convention: library-level changes are
+  silent in activity log).
+- `copyRules(library, field)` — row-clone on
+  `FormFieldService::insertFromLibrary` (addendum Q3 row-copy mandate).
+- `toJsonShape(rules)` — single source of truth for serialising a
+  collection to the canonical flat bag shape consumed by the snapshot
+  writer (`FormSubmissionService::buildSnapshot`) and by API resources
+  (`FormFieldResource`, `FormFieldLibraryResource`,
+  `PublicFormSchemaResource`).
+- `assertSpecsValid(specs)` — public helper the FormRequests invoke in
+  their `after()` hook to reject bad specs at the HTTP boundary before
+  any write lands (strict validator on save, WS-5b commit 3).
+
+**Cascade (`FormFieldChildTablesCascadeObserver`).** Shared observer —
+also cleans up `form_field_bindings` rows (WS-5a) and `form_field_configs`
+rows (WS-5b commit 5). Rules are physical state, not audit: on soft-
+or hard-delete of the owner, the observer physically deletes the rows.
+
+**Activity log events.** Changing a field's rules emits two entries
+on the parent `FormField` subject:
+
+- `field.updated` — payload includes `old.validation_rules` /
+  `new.validation_rules` shapes reconstructed from the relational
+  table via `FormFieldValidationRuleService::toJsonShape()`.
+  Preserves the pre-WS-5b audit-consumer contract for downstream
+  tooling that parses `field.updated` diffs.
+- `field.validation_rules_replaced` — the semantic rule-change event,
+  emitted by `FormFieldValidationRuleService::replaceRules()`.
+
+Both fire for the same semantic change. Aggregate queries over
+activity-log event counts should filter on one, not both — the WS-5a
+precedent (§6.7).
+
+#### 17.4.3 Callback rules
+
+`rule_type = callback` references a named handler registered in
+`config/form_builder.php`:
+
 ```php
 'validation_callbacks' => [
     'kvk_lookup' => \App\Services\Validators\KvkValidator::class,
@@ -2223,7 +2360,55 @@ Registered callbacks in `config/form_builder.php`:
 ],
 ```
 
-Unregistered callbacks rejected at save time.
+The rule row's `parameters.key` must be a key in this map — unregistered
+keys are rejected by `FormFieldValidationRuleService::assertSpecsValid()`
+at save time (WS-5b commit 3 strict validator).
+
+**Legacy `FQCN@method` strings are not accepted.** Pre-WS-5b
+`validation_rules` JSON sometimes stored callbacks as fully-qualified
+class strings (`App\Services\Validators\KvkValidator@validate`). Those
+were never a formal contract and are not portable across refactors.
+Backfill surfaces them as WARN log lines for manual review; operators
+either register the callback under a named key in
+`config/form_builder.php` or drop the reference.
+
+#### 17.4.4 Legacy JSON migration (WS-5b)
+
+The WS-5b backfill migration
+(`2026_04_25_110001_backfill_form_field_validation_rules.php`)
+translates pre-WS-5b JSON keys to relational rows. Strict-enterprise
+dispatch — no guessing, no silent drops for unknown data.
+
+- **Column-duplicates** (`required`, `unique`): WARN-log and skip.
+  The is_* columns are the single sources of truth.
+- **Canonicalisations**: legacy `max_priorities` (SECTION_PRIORITY UI
+  soft cap) collapses to `rule_type = max_selected` — same semantic of
+  "cap on entries in a list-valued field", and two enum cases for one
+  semantic is rot.
+- **Ambiguous `min` / `max`**: dispatched by `field_type`:
+  - NUMBER                   → `min_value` / `max_value`
+  - TEXT/TEXTAREA/EMAIL/PHONE/URL → `min_length` / `max_length`
+  - DATE/DATETIME            → `date_min` / `date_max`
+  - anything else            → **FAIL** the migration.
+  Type-inappropriate uses of `min` / `max` are seed-data bugs.
+- **Non-validation keys** (`tag_categories`, `storage_disk`): skipped
+  with an INFO log line — commit 5's configs-backfill migration picks
+  them up into the separate `form_field_configs` table (ARCH §17.5).
+- **Unknown top-level keys**: **FAIL** the migration. Phase A seed-scan
+  should have caught these; if one slips through we want the crash,
+  not the skip.
+
+Rollback reconstructs the JSON bag using canonical keys (post-rename).
+It does NOT resurrect column-duplicates or non-validation keys — those
+never landed in the relational table. The forward+back pair is safe as
+a unit; a partial rollback that pops this migration but leaves its
+create-table sibling is not a supported state.
+
+Historical snapshots written pre-WS-5b embed the legacy flat bag
+(`validation_rules: {"min": 16, "max": 99, "max_priorities": 3}`).
+Those rows are immutable records and are not rewritten by the
+migration. Snapshot readers must tolerate both shapes — pre-WS-5b
+legacy keys and post-WS-5b canonical keys.
 
 ### 17.5 Webhooks
 

dev-docs/SCHEMA.md

@@ -1,10 +1,23 @@
 # Crewli — Core Database Schema
 
 > Source: Design Document v1.3 — Section 3.5  
-> **Version: 2.2** — Updated April 2026
+> **Version: 2.3** — Updated April 2026
 >
 > **Changelog:**
 >
+> - v2.3: WS-5b (partial) — `form_field_validation_rules` relational table
+>   replaces the `validation_rules` JSON on `form_fields` and
+>   `form_field_library`. Typed `rule_type` column + per-rule `parameters`
+>   JSON; polymorphic morph owner reuses the WS-5a aliases (`form_field`,
+>   `form_field_library`). Canonicalised legacy keys at backfill: ambiguous
+>   `min`/`max` → `min_value`/`max_value`/`min_length`/`max_length`/
+>   `date_min`/`date_max` by field type; `max_priorities` → `max_selected`.
+>   Skipped keys: `required` (is_required column), `unique` (is_unique
+>   column). Non-validation keys (`tag_categories`, `storage_disk`)
+>   deferred to WS-5b commit 5 — they relocate to a separate
+>   `form_field_configs` table (ARCH §17.5) rather than polluting the
+>   validation-rules table. See ARCH-FORM-BUILDER.md §17.4 and
+>   ARCH-CONSOLIDATION-ADDENDUM-2026-04-24 §Q3 WS-5b Uitvoering.
 > - v2.2: WS-5a — `form_field_bindings` relational table replaces
 >   `form_fields.binding` and `form_field_library.default_binding` JSON.
 >   Polymorphic morph owner (`form_field` / `form_field_library`) per
@@ -1967,7 +1980,6 @@ that aggregates the user's submitted, non-test `form_submissions`.
 | `label`                    | string          |                                                                |
 | `help_text`                | text nullable   |                                                                |
 | `options`                  | JSON nullable   | Choice options                                                 |
-| `validation_rules`         | JSON nullable   |                                                                |
 | `default_is_required`      | bool            | default: false                                                 |
 | `default_is_filterable`    | bool            | default: false                                                 |
 | `translations`             | JSON nullable   | Per-locale overrides                                           |
@@ -1977,7 +1989,7 @@ that aggregates the user's submitted, non-test `form_submissions`.
 | `is_active`                | bool            | default: true                                                  |
 | `created_at`, `updated_at` | timestamps      |                                                                |
 
-**Relations:** `belongsTo` organisation; `hasMany` form_fields via `library_field_id`; `morphMany` form_field_bindings as `owner`  
+**Relations:** `belongsTo` organisation; `hasMany` form_fields via `library_field_id`; `morphMany` form_field_bindings as `owner`; `morphMany` form_field_validation_rules as `owner`  
 **Indexes:** `(organisation_id, field_type)`, `(organisation_id, is_active)`  
 **Unique constraint:** `UNIQUE(organisation_id, slug)`  
 **Global scope:** `OrganisationScope`  
@@ -1986,6 +1998,11 @@ that aggregates the user's submitted, non-test `form_submissions`.
 > Bindings moved to the relational `form_field_bindings` table
 > (ARCH-FORM-BUILDER.md §6.7). See WS-5a in
 > `/dev-docs/ARCH-CONSOLIDATION-ADDENDUM-2026-04-24.md` §Q3.
+>
+> Validation rules moved to the relational `form_field_validation_rules`
+> table (ARCH-FORM-BUILDER.md §17.4). The column was dropped in WS-5b;
+> see `/dev-docs/ARCH-CONSOLIDATION-ADDENDUM-2026-04-24.md` §Q3 WS-5b
+> Uitvoering for the full catalogue and migration notes.
 
 ---
 
@@ -2012,7 +2029,6 @@ that aggregates the user's submitted, non-test `form_submissions`.
 | `help_text`                | text nullable      |                                                                                                      |
 | `section`                  | string(100) null   | Visual grouping header (independent of `form_schema_section_id`)                                     |
 | `options`                  | JSON nullable      | Choice options                                                                                       |
-| `validation_rules`         | JSON nullable      | min/max/regex/allowed_mime_types/storage_disk/callback, etc.                                         |
 | `is_required`              | bool               | default: false                                                                                       |
 | `is_filterable`            | bool               | default: false — populates `form_values.value_indexed` / pivot                                       |
 | `is_portal_visible`        | bool               | default: true                                                                                        |
@@ -2029,13 +2045,18 @@ that aggregates the user's submitted, non-test `form_submissions`.
 | `created_at`, `updated_at` | timestamps         |                                                                                                      |
 | `deleted_at`               | timestamp nullable | Soft delete preserves history                                                                        |
 
-**Relations:** `belongsTo` schema, section (nullable), libraryField; `hasMany` form_values; `morphMany` form_field_bindings as `owner`  
+**Relations:** `belongsTo` schema, section (nullable), libraryField; `hasMany` form_values; `morphMany` form_field_bindings as `owner`; `morphMany` form_field_validation_rules as `owner`  
 **Indexes:** `(form_schema_id, sort_order)`, `(form_schema_id, is_filterable)`, `(library_field_id)`, `(form_schema_id, slug)`  
 **Soft delete:** yes
 
 > Bindings moved to the relational `form_field_bindings` table
 > (ARCH-FORM-BUILDER.md §6.7). See WS-5a in
 > `/dev-docs/ARCH-CONSOLIDATION-ADDENDUM-2026-04-24.md` §Q3.
+>
+> Validation rules moved to the relational `form_field_validation_rules`
+> table (ARCH-FORM-BUILDER.md §17.4). The column was dropped in WS-5b;
+> see `/dev-docs/ARCH-CONSOLIDATION-ADDENDUM-2026-04-24.md` §Q3 WS-5b
+> Uitvoering for the full catalogue and migration notes.
 
 ---
 
@@ -2071,6 +2092,38 @@ that aggregates the user's submitted, non-test `form_submissions`.
 
 ---
 
+### `form_field_validation_rules`
+
+> Relational home for field and library-field validation rules. One row
+> per `(owner, rule_type)`. `rule_type` is an app-enforced enum
+> (`FormFieldValidationRuleType`) — database column is `string(40)` so
+> the enum can extend without migration. `parameters` JSON carries per-
+> rule-type configuration (value, pattern, mime_types, etc.); shape is
+> enforced at the service layer, not the DB.
+>
+> Polymorphic owner — morph-map aliases `form_field` and
+> `form_field_library` (reused from WS-5a). Rules are physical state
+> (not audit) — they cascade on owner delete (soft or hard) via the
+> shared `FormFieldChildTablesCascadeObserver`. ARCH §17.4.
+
+| Column              | Type              | Notes                                                                          |
+| ------------------- | ----------------- | ------------------------------------------------------------------------------ |
+| `id`                | ULID              | PK                                                                             |
+| `owner_type`        | string(40)        | morph alias: `form_field` or `form_field_library`                              |
+| `owner_id`          | ULID              | parent row (a `form_fields.id` or `form_field_library.id`)                     |
+| `rule_type`         | string(40)        | `FormFieldValidationRuleType` case (`min_length`, `max_value`, `regex`, `allowed_mime_types`, `callback`, etc.) |
+| `parameters`        | JSON              | Per-rule-type bag (e.g. `{"value": 3}` for `min_length`, `{"mime_types":[...]}` for `allowed_mime_types`) |
+| `error_message_key` | string(100) null  | Optional i18n key for custom rejection message                                 |
+| `created_at`, `updated_at` | timestamps |                                                                                |
+
+**Relations:** `morphTo` owner (`form_field` or `form_field_library`)  
+**Indexes:** `(rule_type)`, `(owner_type, owner_id)`  
+**Unique constraint:** `UNIQUE(owner_type, owner_id, rule_type)`  
+**Global scope:** `FormFieldValidationRuleScope` — sibling to `FormFieldBindingScope`, same UNION shape over both owner chains. Escape hatch: `withoutGlobalScope(FormFieldValidationRuleScope::class)`. Base-class extraction deferred to WS-5d per addendum Q3 (premature abstraction from two siblings is still premature).  
+**Soft delete:** no — rules are current state, not audit
+
+---
+
 ### `form_submissions`
 
 > One submission per `(schema, subject)` in `single` / `draft_single`