docs: BACKLOG + ARCH-BINDINGS appendix + RFC v1.2 for registry alignment (WS-6)

Two new BACKLOG entries capture the deliberate v1 deferrals:

  - ARTIST-ADV-BINDING-MODEL — design how artist_advance form data
    relates to Artist + AdvanceSection entities (when, if ever, an
    Eloquent Artist class is needed, and whether bindings are even
    the right abstraction for OUTPUT-shaped advance forms).

  - FORM-BINDING-JSON-PATH — extend binding registry to support
    JSON-path attributes (custom_fields.dietary_preferences etc).
    For v1 the recommendation is TAG_PICKER + tag_categories config.

ARCH-BINDINGS.md gets an appendix explaining the v1 scope decisions
explicitly: why 'artist' has no registry entries (model class
absent + advance forms are OUTPUT-shaped, not provisioning-shaped),
why JSON-path attributes are out of scope (v1 is column-level only),
and how BindingTypeRegistryConsistencyTest prevents future drift.

RFC-WS-6.md → v1.2 with a §3 Q9 addendum tracking the registry
alignment + the 3 renames, 5 removals, and 1 new column landed in
this branch.

Refs: WS-6 sessie 3a binding-target drift audit, sessie 3a.5 cleanup

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

dev-docs/RFC-WS-6.md

@@ -3,8 +3,8 @@
 ## 1. Status
 
 - **State:** Authoritative for sessions 1, 2, 3 of WS-6
-- **Frozen:** 2026-04-25 (v1.0); refined post-session-2 cleanup as v1.1 (see §10)
-- **Version:** v1.1
+- **Frozen:** 2026-04-25 (v1.0); refined post-session-2 cleanup as v1.1, then again as v1.2 (see §10)
+- **Version:** v1.2
 - **Owner:** Bert Hausmans
 - **Origin:** Architectural session 2026-04-25 (Claude Chat) — 13 design decisions, 4 refinements, 3 observations
 - **Related:**
@@ -278,6 +278,37 @@ create-as-needed fallback chain when seeding event_registration
 schemas, so dev environments don't fail the publish guard out of the
 box.
 
+#### Q9 v1.2 addendum — Registry alignment with model columns
+
+Sessie 3a surfaced that several entries in the `BindingTypeRegistry`
+config did not match actual Eloquent model column names
+(`person.phone_number` vs `phone`, `company.email` vs `contact_email`,
+`company.phone_number` vs `contact_phone`) and that an `Artist` Eloquent
+model class is absent.
+
+Sessie 3a.5 corrected this:
+
+- **Renames** (registry → matches model column): `person.phone_number`
+  → `person.phone`, `company.email` → `company.contact_email`,
+  `company.phone_number` → `company.contact_phone`.
+- **New column**: `companies.kvk_number` (nullable, indexed) added so
+  the registry's B2B identity-key candidate is now legitimately
+  bindable.
+- **Removed entries** (intentional v1 deferrals): `person.dietary_preferences`
+  (custom_fields JSON path; BACKLOG `FORM-BINDING-JSON-PATH`),
+  `artist.email` / `artist.stage_name` / `artist.tech_rider` /
+  `artist.hospitality_rider` (column absent + Artist model absent),
+  and the `artist` entity removed entirely from the registry (BACKLOG
+  `ARTIST-ADV-BINDING-MODEL`).
+- **Drift-prevention test**: `BindingTypeRegistryConsistencyTest`
+  extended with a model-existence + column-existence assertion. Future
+  drift surfaces as a test failure, not a runtime surprise.
+
+`artist_advance` schemas may still exist in v1 with empty
+`required_bindings`; the applicator runs and resolves to an empty
+binding list, COMPLETED state. See ARCH-BINDINGS.md appendix for the
+rationale.
+
 ### Q10 — Section-level submit: stub now, activate later
 
 **Decision:** Build the listener-class structure now; gate the runtime via `config('form_builder.section_apply_enabled', false)`; activate when ARTIST_ADVANCE feature work lands.
@@ -468,3 +499,8 @@ This document. Sessions 2 and 3 reference RFC sections by number rather than re-
   - **§3 Q9 addendum** — `form_schemas.default_crowd_type_id` (nullable ULID, no DB-level FK) replaces the silent `CrowdType::oldest()` heuristic. New `RequiresDefaultCrowdType` publish guard wired into `EventRegistrationGuards`. Runtime failsafe in `PersonProvisioner::resolveCrowdTypeId()`.
   - Snapshot dual-key cleanup (separate from RFC §3): legacy `binding` (singular) snapshot key dropped; `bindings` (plural list) is the single source of truth in `schema_snapshot.fields[*]`. ARCH-BINDINGS.md §6.4 / §6.1 already specified the plural list — code converged.
   - Route model binding (separate from RFC §3): controller-level workaround `$request->route('formSubmissionActionFailure')` replaced with explicit `Route::bind()` in `AppServiceProvider::boot()` plus `->withoutScopedBindings()` on org-scoped routes. Type-hinted parameters restored. RFC V3 (FK-chain tenant policy) unchanged.
+- 2026-04-28 — v1.2 — Registry alignment with model columns (sessie 3a.5):
+  - 3 renames (registry → model): `person.phone_number` → `phone`, `company.email` → `contact_email`, `company.phone_number` → `contact_phone`.
+  - 5 removals (deferred to BACKLOG): `person.dietary_preferences` (FORM-BINDING-JSON-PATH); `artist.email`/`stage_name`/`tech_rider`/`hospitality_rider` plus the `artist` entity itself (ARTIST-ADV-BINDING-MODEL).
+  - 1 new model column: `companies.kvk_number` (nullable, indexed).
+  - `BindingTypeRegistryConsistencyTest` extended with a model-existence + column-existence assertion preventing future drift.