QA hardening: security RLS fixes, Flutter 3.47.5 upgrade, UI/validation fixes

Security — enforce write authorization server-side (was UI/RPC-only):
- it_service_requests RLS: block cross-office read/edit + self-approve (QA-015)
- pass_slips RLS: owner can complete but not self-approve (QA-046)
- swap_requests RLS: scope select/update to participants + admin (QA-047)
- storage: tighten it_service_attachments + task_attachments write/delete (QA-027)
- admin_user_management edge function: allow programmers to manage users (QA-016)

Fixes:
- workforce generator "uncovered shifts" false alarms (QA-043/044)
- network-map VLAN + New-location dialog validation, disabled-until-valid (QA-048)
- de-flake time-of-day-dependent dashboard metrics test (QA-045)

Toolchain:
- upgrade to Flutter 3.47.5 / Dart 3.13.4; font_awesome_flutter 11.0.0,
  flutter_quill 11.6.0, pdfrx 2.6.5; clear resulting deprecations (QA-002)

analyze clean; 139 tests pass; web build succeeds. Report + evidence in docs/qa/.

Note: also carries the in-progress Brick model cleanup already present in the
working tree. QA-001 (AI keys public in the build) is deferred by owner decision.

Co-Authored-By: claude-flow <ruv@ruv.net>

lib/screens/attendance/work_log_tab.dart

@@ -8,14 +8,14 @@ import 'package:intl/intl.dart';
 import 'package:printing/printing.dart';
 import 'package:share_plus/share_plus.dart';
 
-import '../../models/attendance_log.dart';
-import '../../models/it_service_request.dart';
-import '../../models/it_service_request_assignment.dart';
-import '../../models/pass_slip.dart';
-import '../../models/task.dart';
-import '../../models/task_activity_log.dart';
+import '../../models/attendance_log.model.dart';
+import '../../models/it_service_request.model.dart';
+import '../../models/it_service_request_assignment.model.dart';
+import '../../models/pass_slip.model.dart';
+import '../../models/task.model.dart';
+import '../../models/task_activity_log.model.dart';
 import '../../models/task_assignment.dart';
-import '../../models/ticket.dart';
+import '../../models/ticket.model.dart';
 import '../../providers/attendance_provider.dart';
 import '../../providers/it_service_request_provider.dart';
 import '../../providers/pass_slip_provider.dart';
@@ -24,6 +24,7 @@ import '../../providers/tasks_provider.dart';
 import '../../providers/tickets_provider.dart';
 import '../../theme/m3_motion.dart';
 import '../../utils/app_time.dart';
+import '../../utils/snackbar.dart';
 import 'work_log_pdf.dart';
 
 // ─── Domain types ────────────────────────────────────────────────────────────
@@ -674,9 +675,7 @@ class _WorkLogTabState extends ConsumerState<WorkLogTab> {
           }
         } catch (e) {
           if (context.mounted) {
-            ScaffoldMessenger.of(context).showSnackBar(
-              SnackBar(content: Text('Export failed: $e')),
-            );
+            showErrorSnackBar(context, 'Export failed: $e');
           }
         } finally {
           entry.remove();
@@ -691,7 +690,6 @@ class _WorkLogTabState extends ConsumerState<WorkLogTab> {
     String personName,
     String rangeLabel,
   ) async {
-    final messenger = ScaffoldMessenger.of(context);
     try {
       final range = _effectiveDateRange;
       final modeLabel = switch (_viewMode) {
@@ -730,9 +728,7 @@ class _WorkLogTabState extends ConsumerState<WorkLogTab> {
       );
     } catch (e) {
       if (!context.mounted) return;
-      messenger.showSnackBar(
-        SnackBar(content: Text('Export failed: $e')),
-      );
+      showErrorSnackBar(context, 'Export failed: $e');
     }
   }
 
@@ -862,7 +858,6 @@ class _WorkLogTabState extends ConsumerState<WorkLogTab> {
     String personName,
     List<_DailySummaryData> multiDaySummaries,
   ) async {
-    final messenger = ScaffoldMessenger.of(context);
     try {
       late Uint8List bytes;
       if (!_isMultiDay || _isDrilling) {
@@ -901,9 +896,7 @@ class _WorkLogTabState extends ConsumerState<WorkLogTab> {
       );
     } catch (e) {
       if (!context.mounted) return;
-      messenger.showSnackBar(
-        SnackBar(content: Text('Failed to generate PDF: $e')),
-      );
+      showErrorSnackBar(context, 'Failed to generate PDF: $e');
     }
   }