refactor(support): consolidate remaining ID normalization via toIntIds()

Extends the toIntIds() rollout to service and repository layers:

- Drops a third private duplicate (UserCustomFieldValueService::normalizeTenantIds)
- Collapses the two-line intval+filter pattern inside UserAssignmentService,
  UserAuthorizationPolicy, SsoUserLinkService, DepartmentService, and
  UserCustomFieldValueService
- Replaces inline patterns in 4 repositories (RolePermissionRepository,
  RoleAssignableRoleRepository, UserWriteRepository, DepartmentRepository,
  UserCustomFieldValueRepository, UserCustomFieldValueOptionRepository)
- Simplifies the notifications sanitizeTenantIds trait body

Tenant-area files deliberately untouched per parallel ongoing work on
the tenant-logo refactor.

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

core/Service/CustomField/UserCustomFieldValueService.php

@@ -25,7 +25,7 @@ class UserCustomFieldValueService
         if (!$canEdit) {
             return ['ok' => true, 'errors' => []];
         }
-        $tenantIds = self::normalizeTenantIds($tenantIds);
+        $tenantIds = toIntIds($tenantIds);
         if (!$tenantIds) {
             return ['ok' => true, 'errors' => []];
         }
@@ -38,7 +38,7 @@ class UserCustomFieldValueService
 
     public function buildDefinitionsByTenant(array $tenantIds, bool $includeInactive = false): array
     {
-        $tenantIds = self::normalizeTenantIds($tenantIds);
+        $tenantIds = toIntIds($tenantIds);
         if (!$tenantIds) {
             return [];
         }
@@ -83,8 +83,7 @@ class UserCustomFieldValueService
         if ($userId <= 0) {
             return [];
         }
-        $definitionIds = array_values(array_unique(array_map('intval', $definitionIds)));
-        $definitionIds = array_values(array_filter($definitionIds, static fn ($id) => $id > 0));
+        $definitionIds = toIntIds($definitionIds);
         if (!$definitionIds) {
             return [];
         }
@@ -251,7 +250,7 @@ class UserCustomFieldValueService
             return ['ok' => false, 'errors' => [t('User not found')]];
         }
 
-        $tenantIds = self::normalizeTenantIds($tenantIds);
+        $tenantIds = toIntIds($tenantIds);
         // Always clean values for tenants no longer assigned — happens even when !$canEdit,
         // because orphaned custom field data should not persist after tenant reassignment.
         if (!$this->valueRepository->deleteByUserOutsideTenantIds($userId, $tenantIds)) {
@@ -541,12 +540,6 @@ class UserCustomFieldValueService
         return $this->userScopeGateway;
     }
 
-    private static function normalizeTenantIds(array $tenantIds): array
-    {
-        $tenantIds = array_values(array_unique(array_map('intval', $tenantIds)));
-        return array_values(array_filter($tenantIds, static fn ($id) => $id > 0));
-    }
-
     private static function normalizeBool($value): ?int
     {
         if (is_bool($value)) {