feat(form-builder): add core services (schema, field, submission, value, field-access, locale, tag-sync, filter, webhook, anonymisation)

S2b Phase 1 per ARCH-FORM-BUILDER.md §20.2. Ten services + supporting
exceptions, jobs, and the organisations.default_locale column needed by
FormLocaleResolver. All services log via spatie/laravel-activitylog, write
operations are transactional, queued jobs are idempotent.

- FormSchemaService: CRUD, slug, version bump, duplicate, edit-lock,
  public_token rotation (7-day grace window), typed-confirmation delete.
- FormFieldService: CRUD, reorder, insertFromLibrary, binding-change guard
  (§6.5), conditional_logic + section cycle detection (§8, §4.8.1),
  is_filterable toggle triggers BackfillFormValueIndexedJob (§7.2, §22.10).
- FormSubmissionService: createDraft with idempotency, saveDraft (auto-save),
  submit with schema snapshot + signature hash computation (§9), review,
  delegate/revoke, soft delete. Fires S1 domain events (§17.1).
- FormValueService: bulk upsert with FieldAccessService RBAC (§24.2),
  Pattern A/C entity mirror writes (§6.1, §6.6) with cross-entity graceful
  skip for person.user_id=null.
- FieldAccessService: canRead/canWrite/filterVisibleFields honouring
  role_restrictions + subject-self (§18.3, §24.1).
- FormLocaleResolver: submitter → schema → org.default_locale → 'nl' (§16.2).
- FormTagSyncService: rebuildForPerson — replaces legacy TagSyncService
  deleted in S2a (§31.10).
- FilterQueryBuilder: generic filter applier for entity_column / tags /
  form_field sources (§7.4–§7.5).
- FormWebhookDispatcher + DeliverFormWebhookJob: HMAC-signed delivery with
  SSRF protection, exponential backoff {1m,5m,30m,2h,8h}, max 5 attempts,
  dead-letter on exhaustion (§17.5).
- FormSubmissionAnonymisationService: per-field anonymisation with separate
  activity log entries (§13.3, §23.4).

MigrationRollbackTest: pin the S2a drop migration by filename so future
migrations don't shift the step offset.

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

api/app/Services/FormBuilder/FormWebhookDispatcher.php

@@ -0,0 +1,86 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Services\FormBuilder;
+
+use App\Enums\FormBuilder\FormWebhookDeliveryStatus;
+use App\Jobs\FormBuilder\DeliverFormWebhookJob;
+use App\Models\FormBuilder\FormSchemaWebhook;
+use App\Models\FormBuilder\FormSubmission;
+use App\Models\FormBuilder\FormWebhookDelivery;
+
+/**
+ * Finds active webhooks for a submission's schema + trigger and queues a
+ * DeliverFormWebhookJob per delivery row (ARCH §17.5.2).
+ */
+final class FormWebhookDispatcher
+{
+    public function dispatchForSubmission(FormSubmission $submission, string $triggerEvent): void
+    {
+        if ($submission->is_test) {
+            return;
+        }
+
+        $webhooks = FormSchemaWebhook::query()
+            ->where('form_schema_id', $submission->form_schema_id)
+            ->where('trigger_event', $triggerEvent)
+            ->where('is_active', true)
+            ->get();
+
+        foreach ($webhooks as $webhook) {
+            /** @var FormWebhookDelivery $delivery */
+            $delivery = FormWebhookDelivery::create([
+                'form_schema_webhook_id' => $webhook->id,
+                'form_submission_id' => $submission->id,
+                'trigger_event' => $triggerEvent,
+                'status' => FormWebhookDeliveryStatus::PENDING->value,
+                'attempts' => 0,
+                'payload_snapshot' => $this->buildPayload($submission, $triggerEvent),
+            ]);
+
+            DeliverFormWebhookJob::dispatch($delivery->id)->onConnection('webhooks')->onQueue('webhooks');
+        }
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    private function buildPayload(FormSubmission $submission, string $triggerEvent): array
+    {
+        $submission->loadMissing(['schema', 'schema.organisation', 'values.field']);
+
+        $values = [];
+        foreach ($submission->values as $value) {
+            if ($value->field?->slug) {
+                $values[$value->field->slug] = $value->value;
+            }
+        }
+
+        return [
+            'event' => 'form_submission.'.$triggerEvent,
+            'triggered_at' => now()->toIso8601String(),
+            'organisation' => [
+                'id' => $submission->schema?->organisation?->id,
+                'name' => $submission->schema?->organisation?->name,
+                'slug' => $submission->schema?->organisation?->slug,
+            ],
+            'schema' => [
+                'id' => $submission->schema?->id,
+                'purpose' => $submission->schema?->purpose instanceof \BackedEnum
+                    ? $submission->schema->purpose->value
+                    : $submission->schema?->purpose,
+                'slug' => $submission->schema?->slug,
+                'version' => $submission->schema?->version,
+            ],
+            'submission' => [
+                'id' => $submission->id,
+                'subject_type' => $submission->subject_type,
+                'subject_id' => $submission->subject_id,
+                'submitted_at' => optional($submission->submitted_at)->toIso8601String(),
+                'submitted_by_user_id' => $submission->submitted_by_user_id,
+                'values' => $values,
+            ],
+        ];
+    }
+}