feat(approvals): Approval Flow v2 프런트엔드 전면 개편

- 환경/라우터 모듈에 approval_flow_v2 토글을 추가하고 FeatureFlags 초기화를 연결 (.env*, lib/core/**)
- ApiClient 빌더·ApiRoutes 확장과 ApprovalRepositoryRemote 리팩터링으로 include·액션 시그니처를 정합화
- ApprovalFlow·ApprovalDraft 엔티티/레포/유즈케이스를 도입해 서버 초안과 단계 액션(승인·회수·재상신)을 지원
- Approval 컨트롤러·히스토리·템플릿 페이지와 공유 위젯을 재작성해 감사 로그·회수 UX·템플릿 CRUD를 반영
- Inbound/Outbound/Rental 컨트롤러·페이지에 결재 섹션을 삽입하고 대시보드 pending 카드 요약을 갱신
- SuperportDialog·FormField 등 공통 위젯을 보강하고 승인 위젯 가이드를 추가해 UI 가이드를 정리
- 결재/재고 테스트 픽스처와 단위·위젯·통합 테스트를 확장하고 flutter_test_config로 스테이징 호스트를 허용
- Approval Flow 레포트/플랜 문서를 업데이트하고 ApprovalFlow_System_Integration_and_ChangePlan.md를 추가
- 실행: flutter analyze, flutter test

test/features/approvals/approval_page_permission_test.dart

@@ -18,14 +18,38 @@ import 'package:superport_v2/features/inventory/lookups/domain/entities/lookup_i
 import 'package:superport_v2/features/inventory/lookups/domain/repositories/inventory_lookup_repository.dart';
 
 import '../../helpers/test_app.dart';
+import '../../helpers/fixture_loader.dart';
 
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
 
+  late Map<String, dynamic> permissionFixture;
+  late Set<PermissionAction> viewerPermissions;
+  late Set<PermissionAction> approverPermissions;
+
+  Set<PermissionAction> parseActions(String key) {
+    final raw = permissionFixture[key];
+    if (raw is! List) {
+      return {};
+    }
+    return raw
+        .whereType<String>()
+        .map(
+          (action) => PermissionAction.values.firstWhere(
+            (candidate) => candidate.name == action,
+            orElse: () => PermissionAction.view,
+          ),
+        )
+        .toSet();
+  }
+
   setUpAll(() async {
     dotenv.testLoad(fileInput: 'FEATURE_APPROVALS_ENABLED=true');
     await Environment.initialize();
     dotenv.env['FEATURE_APPROVALS_ENABLED'] = 'true';
+    permissionFixture = loadJsonFixture('approvals/approval_permissions.json');
+    viewerPermissions = parseActions('viewer');
+    approverPermissions = parseActions('approver');
   });
 
   tearDown(() async {
@@ -52,9 +76,7 @@ void main() {
     GetIt.I.registerSingleton<InventoryLookupRepository>(lookupRepo);
 
     final permissionManager = PermissionManager(
-      overrides: {
-        PermissionResources.approvals: {PermissionAction.view},
-      },
+      overrides: {PermissionResources.approvals: viewerPermissions},
     );
 
     final view = tester.view;
@@ -95,12 +117,7 @@ void main() {
     GetIt.I.registerSingleton<InventoryLookupRepository>(lookupRepo);
 
     final permissionManager = PermissionManager(
-      overrides: {
-        PermissionResources.approvals: {
-          PermissionAction.view,
-          PermissionAction.approve,
-        },
-      },
+      overrides: {PermissionResources.approvals: approverPermissions},
     );
 
     await pumpApprovalPage(tester, permissionManager);
@@ -133,12 +150,7 @@ void main() {
     GetIt.I.registerSingleton<InventoryLookupRepository>(lookupRepo);
 
     final permissionManager = PermissionManager(
-      overrides: {
-        PermissionResources.approvals: {
-          PermissionAction.view,
-          PermissionAction.approve,
-        },
-      },
+      overrides: {PermissionResources.approvals: approverPermissions},
     );
 
     await pumpApprovalPage(tester, permissionManager);
@@ -200,6 +212,8 @@ class _StubApprovalRepository implements ApprovalRepository {
     int? transactionId,
     int? approvalStatusId,
     int? requestedById,
+    List<String>? statusCodes,
+    bool includePending = false,
     bool includeHistories = false,
     bool includeSteps = false,
   }) async {
@@ -220,6 +234,31 @@ class _StubApprovalRepository implements ApprovalRepository {
     return _approval;
   }
 
+  @override
+  Future<Approval> submit(ApprovalSubmissionInput input) async {
+    return _approval;
+  }
+
+  @override
+  Future<Approval> resubmit(ApprovalResubmissionInput input) async {
+    return _approval;
+  }
+
+  @override
+  Future<Approval> approve(ApprovalDecisionInput input) async {
+    return _approval;
+  }
+
+  @override
+  Future<Approval> reject(ApprovalDecisionInput input) async {
+    return _approval;
+  }
+
+  @override
+  Future<Approval> recall(ApprovalRecallInput input) async {
+    return _approval;
+  }
+
   @override
   Future<List<ApprovalAction>> listActions({bool activeOnly = true}) async {
     return [
@@ -229,6 +268,24 @@ class _StubApprovalRepository implements ApprovalRepository {
     ];
   }
 
+  @override
+  Future<PaginatedResult<ApprovalHistory>> listHistory({
+    required int approvalId,
+    int page = 1,
+    int pageSize = 20,
+    DateTime? from,
+    DateTime? to,
+    int? actorId,
+    int? approvalActionId,
+  }) async {
+    return PaginatedResult(
+      items: const <ApprovalHistory>[],
+      page: page,
+      pageSize: pageSize,
+      total: 0,
+    );
+  }
+
   @override
   Future<Approval> performStepAction(ApprovalStepActionInput input) async {
     return _approval;