feat(receipt-import): add refresh categories endpoint and UI integration

Co-authored-by: Copilot <copilot@github.com>

flutter/lib/features/profile/data/profile_repository.dart

@@ -41,4 +41,12 @@ class ProfileRepository {
     );
     return UserProfile.fromJson(data);
   }
+
+  Future<void> refreshCategories() async {
+    final token = await _ref.read(authStateProvider.future);
+    await guardedApiCall(
+      _ref,
+      () => _apiClient.postJson(ReceiptImportApiPaths.refreshCategories, body: {}, token: token),
+    );
+  }
 }

flutter/lib/features/profile/presentation/profile_screen.dart

@@ -27,6 +27,7 @@ class _ProfileScreenState extends ConsumerState<ProfileScreen> {
   final _formKey = GlobalKey<FormState>();
   bool _isLoading = true;
   bool _isSaving = false;
+  bool _isRefreshingCategories = false;
   String? _error;
   UserProfile? _profile;
   _ProfileTab _activeTab = _ProfileTab.profile;
@@ -105,6 +106,24 @@ class _ProfileScreenState extends ConsumerState<ProfileScreen> {
     context.go('/login');
   }
 
+  Future<void> _refreshCategories() async {
+    setState(() => _isRefreshingCategories = true);
+    try {
+      await ref.read(profileRepositoryProvider).refreshCategories();
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(content: Text('Kategorier har uppdaterats.')),
+      );
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(mapErrorToUserMessage(e, context))),
+      );
+    } finally {
+      if (mounted) setState(() => _isRefreshingCategories = false);
+    }
+  }
+
   List<_ProfileTab> _visibleTabs(bool isAdmin) {
     return [
       _ProfileTab.profile,
@@ -212,6 +231,23 @@ class _ProfileScreenState extends ConsumerState<ProfileScreen> {
                   : Text(context.l10n.profileSaveAction),
             ),
           ),
+          const SizedBox(height: 16),
+          const Divider(),
+          const SizedBox(height: 8),
+          SizedBox(
+            width: double.infinity,
+            child: OutlinedButton.icon(
+              onPressed: _isRefreshingCategories ? null : _refreshCategories,
+              icon: _isRefreshingCategories
+                  ? const SizedBox(
+                      height: 16,
+                      width: 16,
+                      child: CircularProgressIndicator(strokeWidth: 2),
+                    )
+                  : const Icon(Icons.refresh),
+              label: const Text('Uppdatera kategorier'),
+            ),
+          ),
         ],
       ),
     );