Initial commit: Fabled Android app

Flutter Android client for FabledAssistant with:
- Session-cookie auth via persistent cookie jar (Dio + cookie_jar)
- OAuth/SSO login via in-app WebView (flutter_inappwebview)
- Notes: list, detail (markdown render), create/edit
- Tasks: list with status tabs, create/edit with priority
- Chat: SSE streaming bubbles, conversation management
- Quick Capture FAB for rapid note/task creation
- Settings screen (change server URL, logout)
- Android home screen widget → opens chat
- Riverpod state management, go_router navigation

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/screens/settings/settings_screen.dart

@@ -0,0 +1,39 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
+
+import '../../core/constants.dart';
+import '../../providers/auth_provider.dart';
+import '../../providers/settings_provider.dart';
+
+class SettingsScreen extends ConsumerWidget {
+  const SettingsScreen({super.key});
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final serverUrl = ref.watch(serverUrlProvider);
+
+    return Scaffold(
+      appBar: AppBar(title: const Text('Settings')),
+      body: ListView(
+        children: [
+          ListTile(
+            title: const Text('Server URL'),
+            subtitle: Text(serverUrl ?? 'Not configured'),
+            leading: const Icon(Icons.dns),
+            onTap: () => context.go(Routes.setup),
+          ),
+          const Divider(),
+          ListTile(
+            title: const Text('Sign Out'),
+            leading: const Icon(Icons.logout),
+            onTap: () async {
+              await ref.read(authProvider.notifier).logout();
+              if (context.mounted) context.go(Routes.login);
+            },
+          ),
+        ],
+      ),
+    );
+  }
+}