feat(form-builder): retry history table + integration (WS-6)

Per-attempt retry history (timestamp, user, outcome, exception detail
if failed) replaces the counter-only retry_count tracking.

Changes:

- New `form_submission_action_failure_retry_attempts` table (cascade on
  parent delete, nullOnDelete on user). Explicit short FK names
  (`fsafra_failure_fk`, `fsafra_user_fk`) — auto-generated names exceed
  MySQL's 64-char identifier limit.
- New FormSubmissionActionFailureRetryAttempt model + factory +
  succeeded() state.
- Parent FormSubmissionActionFailure gets retryAttempts() HasMany
  relation (latest('attempted_at')).
- New FormFailureRetryService centralises the retry-flow logic. Both
  the API controller and the artisan command delegate to it. Service
  writes a retry_attempt record per attempt; parent's retry_count
  stays as denormalised cache for index-view performance.
- Successful retry: attempt(succeeded) + parent.retry_count++ +
  parent.resolved_at + parent.resolved_by_user_id + parent.resolved_note
  ("Geslaagde retry door {actor.name}" or "Geslaagde retry
  (geautomatiseerd)" for command-line invocation without an actor).
- Failed retry: attempt(failed) with NEW exception details +
  parent.retry_count++. Parent's exception_class/_message stay
  audit-immutable — they represent the FIRST failure.
- canBeRetried() now correctly checks both resolved_at AND
  dismissed_at (sessie 2's open question Q2 closure).
- New FailureNotRetriableException (controller → 422) and
  ParentSubmissionGoneException (controller → 410) for cleaner
  flow control.

12 new tests:
- FormSubmissionActionFailureRetryAttemptTest (5 unit tests)
- RetryFlowProducesRetryAttemptsTest (7 integration tests covering
  succeeded path, failed path, resolved/dismissed blocking,
  multiple-retries chronological ordering, canBeRetried truth tables)

Pre-existing tests touched:
- FormSubmissionActionFailureTest::test_can_be_retried_only_for_open_state
  — updated to reflect Q2 closure (resolved now blocks too).
- Ws6FoundationMigrationTest::test_down_methods_clean_up_columns_and_table
  — child table must drop before parent (FK constraint).
- 5 backfill test step-counts bumped +1 (new migration sits at top).

SCHEMA.md → v2.9. Schema dump regenerated.

Refs: RFC-WS-6.md §3 Q5 addendum, sessie 2 Q2

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

api/database/schema/mysql-schema.sql

@@ -111,7 +111,7 @@ CREATE TABLE `companies` (
   `organisation_id` char(26) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
   `name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
   `type` enum('supplier','partner','agency','venue','other') CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
-  `kvk_number` varchar(255) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
+  `kvk_number` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci DEFAULT NULL,
   `contact_first_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci DEFAULT NULL,
   `contact_last_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci DEFAULT NULL,
   `contact_email` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci DEFAULT NULL,
@@ -624,6 +624,26 @@ CREATE TABLE `form_schemas` (
   CONSTRAINT `form_schemas_organisation_id_foreign` FOREIGN KEY (`organisation_id`) REFERENCES `organisations` (`id`) ON DELETE CASCADE
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 /*!40101 SET character_set_client = @saved_cs_client */;
+DROP TABLE IF EXISTS `form_submission_action_failure_retry_attempts`;
+/*!40101 SET @saved_cs_client     = @@character_set_client */;
+/*!50503 SET character_set_client = utf8mb4 */;
+CREATE TABLE `form_submission_action_failure_retry_attempts` (
+  `id` char(26) COLLATE utf8mb4_unicode_ci NOT NULL,
+  `form_submission_action_failure_id` char(26) COLLATE utf8mb4_unicode_ci NOT NULL,
+  `attempted_at` timestamp NOT NULL,
+  `attempted_by_user_id` char(26) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
+  `outcome` enum('succeeded','failed') COLLATE utf8mb4_unicode_ci NOT NULL,
+  `exception_class` varchar(255) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
+  `exception_message` text COLLATE utf8mb4_unicode_ci,
+  `created_at` timestamp NULL DEFAULT NULL,
+  `updated_at` timestamp NULL DEFAULT NULL,
+  PRIMARY KEY (`id`),
+  KEY `fsafra_user_fk` (`attempted_by_user_id`),
+  KEY `fsafra_failure_attempt_idx` (`form_submission_action_failure_id`,`attempted_at`),
+  CONSTRAINT `fsafra_failure_fk` FOREIGN KEY (`form_submission_action_failure_id`) REFERENCES `form_submission_action_failures` (`id`) ON DELETE CASCADE,
+  CONSTRAINT `fsafra_user_fk` FOREIGN KEY (`attempted_by_user_id`) REFERENCES `users` (`id`) ON DELETE SET NULL
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+/*!40101 SET character_set_client = @saved_cs_client */;
 DROP TABLE IF EXISTS `form_submission_action_failures`;
 /*!40101 SET @saved_cs_client     = @@character_set_client */;
 /*!50503 SET character_set_client = utf8mb4 */;
@@ -1750,3 +1770,4 @@ INSERT INTO `migrations` (`id`, `migration`, `batch`) VALUES (153,'2026_04_27_10
 INSERT INTO `migrations` (`id`, `migration`, `batch`) VALUES (154,'2026_04_27_100002_drop_form_field_options_json_columns',2);
 INSERT INTO `migrations` (`id`, `migration`, `batch`) VALUES (155,'2026_04_28_100000_restore_default_crowd_type_id_foreign_key',2);
 INSERT INTO `migrations` (`id`, `migration`, `batch`) VALUES (156,'2026_04_28_140000_add_kvk_number_to_companies_table',3);
+INSERT INTO `migrations` (`id`, `migration`, `batch`) VALUES (157,'2026_04_28_180000_create_form_submission_action_failure_retry_attempts_table',4);