M3 Overhaul

lib/screens/tasks/tasks_list_screen.dart

@@ -1,6 +1,7 @@
 import 'dart:async';
 
 import 'package:flutter/material.dart';
+import '../../theme/m3_motion.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_typeahead/flutter_typeahead.dart';
@@ -554,7 +555,7 @@ class _TasksListScreenState extends ConsumerState<TasksListScreen>
             right: 16,
             bottom: 16,
             child: SafeArea(
-              child: FloatingActionButton.extended(
+              child: M3ExpandedFab(
                 onPressed: () => _showCreateTaskDialog(context, ref),
                 icon: const Icon(Icons.add),
                 label: const Text('New Task'),
@@ -588,7 +589,7 @@ class _TasksListScreenState extends ConsumerState<TasksListScreen>
     var showTitleGemini = false;
     Timer? titleTypingTimer;
 
-    await showDialog<void>(
+    await m3ShowDialog<void>(
       context: context,
       builder: (dialogContext) {
         bool saving = false;
@@ -1099,8 +1100,11 @@ class _StatusSummaryCard extends StatelessWidget {
       _ => scheme.onSurfaceVariant,
     };
 
+    // M3 Expressive: filled card with semantic tonal color, no shadow.
     return Card(
       color: background,
+      elevation: 0,
+      shadowColor: Colors.transparent,
       // summary cards are compact — use compact token for consistent density
       shape: AppSurfaces.of(context).compactShape,
       child: Padding(