refactor(auth): migrate to unified auth providers and simplify user retrieval

lib/features/chat/views/chat_page.dart

@@ -12,6 +12,7 @@ import '../../../shared/widgets/responsive_drawer_layout.dart';
 import '../../navigation/widgets/chats_drawer.dart';
 import 'dart:async';
 import '../../../core/providers/app_providers.dart';
+import '../../auth/providers/unified_auth_providers.dart';
 import '../providers/chat_providers.dart';
 import '../../../core/utils/debug_logger.dart';
 import '../../../core/utils/user_display_name.dart';
@@ -1122,12 +1123,12 @@ class _ChatPageState extends ConsumerState<ChatPage> {
 
   Widget _buildEmptyState(ThemeData theme) {
     final l10n = AppLocalizations.of(context)!;
-    final currentUserAsync = ref.watch(currentUserProvider);
-    final userFromProfile = currentUserAsync.maybeWhen(
-      data: (user) => user,
-      orElse: () => null,
+    final authUser = ref.watch(currentUserProvider2);
+    final asyncUser = ref.watch(currentUserProvider);
+    final user = asyncUser.maybeWhen(
+      data: (value) => value ?? authUser,
+      orElse: () => authUser,
     );
-    final user = userFromProfile;
     String? greetingName;
     if (user != null) {
       final derived = deriveUserDisplayName(user, fallback: '').trim();

lib/features/navigation/widgets/chats_drawer.dart

@@ -8,6 +8,7 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
 
 import '../../../core/providers/app_providers.dart';
+import '../../auth/providers/unified_auth_providers.dart';
 import '../../../shared/theme/theme_extensions.dart';
 import '../../chat/providers/chat_providers.dart' as chat;
 // import '../../files/views/files_page.dart';
@@ -1477,12 +1478,7 @@ class _ChatsDrawerState extends ConsumerState<ChatsDrawer> {
   Widget _buildBottomSection(BuildContext context) {
     final theme = context.conduitTheme;
     final sidebarTheme = context.sidebarTheme;
-    final currentUserAsync = ref.watch(currentUserProvider);
-    final userFromProfile = currentUserAsync.maybeWhen(
-      data: (u) => u,
-      orElse: () => null,
-    );
-    final user = userFromProfile;
+    final user = ref.watch(currentUserProvider2);
     final api = ref.watch(apiServiceProvider);
 
     String initialFor(String name) {

lib/features/onboarding/views/onboarding_sheet.dart

@@ -4,7 +4,7 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_animate/flutter_animate.dart';
 import 'package:conduit/l10n/app_localizations.dart';
 
-import '../../../core/providers/app_providers.dart';
+import '../../auth/providers/unified_auth_providers.dart';
 import '../../../core/utils/user_display_name.dart';
 import '../../../shared/theme/theme_extensions.dart';
 import '../../../shared/widgets/sheet_handle.dart';
@@ -67,12 +67,7 @@ class _OnboardingSheetState extends ConsumerState<OnboardingSheet> {
   Widget build(BuildContext context) {
     final height = MediaQuery.of(context).size.height;
     final l10n = AppLocalizations.of(context)!;
-    final currentUserAsync = ref.watch(currentUserProvider);
-    final userFromProfile = currentUserAsync.maybeWhen(
-      data: (user) => user,
-      orElse: () => null,
-    );
-    final user = userFromProfile;
+    final user = ref.watch(currentUserProvider2);
     final greetingName = deriveUserDisplayName(user);
     final pages = _buildPages(l10n, greetingName);
     final pageCount = pages.length;

lib/features/profile/views/profile_page.dart

@@ -41,40 +41,23 @@ class ProfilePage extends ConsumerWidget {
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
-    final user = ref.watch(currentUserProvider);
+    final user = ref.watch(currentUserProvider2);
+    final isAuthLoading = ref.watch(isAuthLoadingProvider2);
     final api = ref.watch(apiServiceProvider);
 
-    return ErrorBoundary(
-      child: user.when(
-        data: (userData) => _buildScaffold(
-          context,
-          body: _buildProfileBody(context, ref, userData, api),
-        ),
-        loading: () => _buildScaffold(
-          context,
-          body: _buildCenteredState(
+    Widget body;
+    if (isAuthLoading && user == null) {
+      body = _buildCenteredState(
         context,
         ImprovedLoadingState(
           message: AppLocalizations.of(context)!.loadingProfile,
         ),
-          ),
-        ),
-        error: (error, stack) => _buildScaffold(
-          context,
-          body: _buildCenteredState(
-            context,
-            ImprovedEmptyState(
-              title: AppLocalizations.of(context)!.unableToLoadProfile,
-              subtitle: AppLocalizations.of(context)!.pleaseCheckConnection,
-              icon: UiUtils.platformIcon(
-                ios: CupertinoIcons.exclamationmark_triangle,
-                android: Icons.error_outline,
-              ),
-            ),
-          ),
-        ),
-      ),
       );
+    } else {
+      body = _buildProfileBody(context, ref, user, api);
+    }
+
+    return ErrorBoundary(child: _buildScaffold(context, body: body));
   }
 
   Scaffold _buildScaffold(BuildContext context, {required Widget body}) {