M3 Overhaul

lib/widgets/app_shell.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import '../theme/m3_motion.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
 // showcaseview removed due to null-safety incompatibility; onboarding shown via dialog
@@ -7,6 +8,7 @@ import '../providers/auth_provider.dart';
 import '../providers/notifications_provider.dart';
 import '../providers/profile_provider.dart';
 import 'app_breakpoints.dart';
+import 'profile_avatar.dart';
 
 final GlobalKey notificationBellKey = GlobalKey();
 
@@ -49,7 +51,7 @@ class AppScaffold extends ConsumerWidget {
       appBar: AppBar(
         title: Row(
           children: [
-            const Icon(Icons.memory),
+            Image.asset('assets/tasq_ico.png', width: 28, height: 28),
             const SizedBox(width: 8),
             Text('TasQ'),
           ],
@@ -73,7 +75,7 @@ class AppScaffold extends ConsumerWidget {
                 padding: const EdgeInsets.symmetric(horizontal: 12),
                 child: Row(
                   children: [
-                    const Icon(Icons.account_circle),
+                    ProfileAvatar(fullName: displayName, radius: 16),
                     const SizedBox(width: 8),
                     Text(displayName),
                     const SizedBox(width: 4),
@@ -89,7 +91,7 @@ class AppScaffold extends ConsumerWidget {
                 IconButton(
                   tooltip: 'Profile',
                   onPressed: () => context.go('/profile'),
-                  icon: const Icon(Icons.account_circle),
+                  icon: ProfileAvatar(fullName: displayName, radius: 16),
                 ),
                 IconButton(
                   tooltip: 'Sign out',
@@ -164,23 +166,44 @@ class AppNavigationRail extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final currentIndex = _currentIndex(location, items);
+    final cs = Theme.of(context).colorScheme;
+
+    // M3 Expressive: tonal surface container instead of a hard border divider.
     return Container(
-      decoration: BoxDecoration(
-        color: Theme.of(context).colorScheme.surface,
-        border: Border(
-          right: BorderSide(
-            color: Theme.of(context).colorScheme.outlineVariant,
-          ),
-        ),
-      ),
+      decoration: BoxDecoration(color: cs.surfaceContainerLow),
       child: NavigationRail(
+        backgroundColor: Colors.transparent,
         extended: extended,
         selectedIndex: currentIndex,
         onDestinationSelected: (value) {
           items[value].onTap(context, onLogout: onLogout);
         },
-        leading: const SizedBox.shrink(),
-        trailing: const SizedBox.shrink(),
+        leading: Padding(
+          padding: EdgeInsets.symmetric(
+            vertical: extended ? 12 : 8,
+            horizontal: extended ? 16 : 0,
+          ),
+          child: Center(
+            child: Image.asset(
+              'assets/tasq_ico.png',
+              width: extended ? 48 : 40,
+              height: extended ? 48 : 40,
+            ),
+          ),
+        ),
+        trailing: Expanded(
+          child: Align(
+            alignment: Alignment.bottomCenter,
+            child: Padding(
+              padding: const EdgeInsets.only(bottom: 16),
+              child: IconButton(
+                tooltip: 'Sign out',
+                onPressed: onLogout,
+                icon: const Icon(Icons.logout),
+              ),
+            ),
+          ),
+        ),
         destinations: [
           for (final item in items)
             NavigationRailDestination(
@@ -256,6 +279,8 @@ class _NotificationBell extends ConsumerWidget {
   }
 }
 
+/// M3 Expressive shell background — uses a subtle tonal surface tint
+/// rather than a gradient to create the organic, seed-colored feel.
 class _ShellBackground extends StatelessWidget {
   const _ShellBackground({required this.child});
 
@@ -263,17 +288,8 @@ class _ShellBackground extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return Container(
-      decoration: BoxDecoration(
-        gradient: LinearGradient(
-          begin: Alignment.topLeft,
-          end: Alignment.bottomRight,
-          colors: [
-            Theme.of(context).colorScheme.surface,
-            Theme.of(context).colorScheme.surfaceContainerLowest,
-          ],
-        ),
-      ),
+    return ColoredBox(
+      color: Theme.of(context).scaffoldBackgroundColor,
       child: child,
     );
   }
@@ -531,9 +547,8 @@ Future<void> _showOverflowSheet(
   List<NavItem> items,
   VoidCallback onLogout,
 ) async {
-  await showModalBottomSheet<void>(
+  await m3ShowBottomSheet<void>(
     context: context,
-    showDragHandle: true,
     builder: (context) {
       return SafeArea(
         child: ListView(