feat(02-03): build task list screen with task row, completion, and overdue highlighting

- TaskListScreen with room name in AppBar, edit/delete room actions
- AsyncValue.when for loading/error/data states with empty state
- TaskRow with leading checkbox, name, German relative due date, frequency label
- Overdue dates highlighted in warm coral (0xFFE07A5F)
- Checkbox marks done immediately (optimistic UI, no undo)
- Row tap navigates to edit form, long-press shows delete confirmation
- FAB for creating new tasks
- ListView.builder for task list sorted by due date

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

lib/features/tasks/presentation/task_row.dart

@@ -0,0 +1,106 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
+
+import 'package:household_keeper/core/database/database.dart';
+import 'package:household_keeper/features/tasks/domain/frequency.dart';
+import 'package:household_keeper/features/tasks/domain/relative_date.dart';
+import 'package:household_keeper/features/tasks/presentation/task_providers.dart';
+
+/// Warm coral/terracotta color for overdue due date text.
+const _overdueColor = Color(0xFFE07A5F);
+
+/// A single task row with leading checkbox, name, relative due date,
+/// and frequency label.
+///
+/// Per user decisions:
+/// - Checkbox marks task done immediately (optimistic UI, no undo)
+/// - Row tap opens edit form
+/// - No swipe gesture
+/// - No effort indicator or description preview on list view
+/// - Overdue: due date text turns warm coral, rest stays normal
+class TaskRow extends ConsumerWidget {
+  const TaskRow({
+    super.key,
+    required this.task,
+    this.onDelete,
+  });
+
+  final Task task;
+  final VoidCallback? onDelete;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final theme = Theme.of(context);
+    final now = DateTime.now();
+    final today = DateTime(now.year, now.month, now.day);
+
+    // Check if task is overdue (due date is before today)
+    final dueDate = DateTime(
+      task.nextDueDate.year,
+      task.nextDueDate.month,
+      task.nextDueDate.day,
+    );
+    final isOverdue = dueDate.isBefore(today);
+
+    // Format relative due date in German
+    final relativeDateText = formatRelativeDate(task.nextDueDate, now);
+
+    // Build frequency label
+    final freq = FrequencyInterval(
+      intervalType: task.intervalType,
+      days: task.intervalDays,
+    );
+    final frequencyText = freq.label();
+
+    return ListTile(
+      leading: Checkbox(
+        value: false, // Always unchecked -- completion is immediate + reschedule
+        onChanged: (_) {
+          // Mark done immediately (optimistic UI, no undo per user decision)
+          ref.read(taskActionsProvider.notifier).completeTask(task.id);
+        },
+      ),
+      title: Text(
+        task.name,
+        style: theme.textTheme.titleMedium,
+        maxLines: 1,
+        overflow: TextOverflow.ellipsis,
+      ),
+      subtitle: Row(
+        children: [
+          Text(
+            relativeDateText,
+            style: theme.textTheme.bodySmall?.copyWith(
+              color: isOverdue ? _overdueColor : theme.colorScheme.onSurfaceVariant,
+            ),
+          ),
+          Padding(
+            padding: const EdgeInsets.symmetric(horizontal: 6),
+            child: Text(
+              '\u00b7', // middle dot separator
+              style: theme.textTheme.bodySmall?.copyWith(
+                color: theme.colorScheme.onSurfaceVariant,
+              ),
+            ),
+          ),
+          Flexible(
+            child: Text(
+              frequencyText,
+              style: theme.textTheme.bodySmall?.copyWith(
+                color: theme.colorScheme.onSurfaceVariant,
+              ),
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+            ),
+          ),
+        ],
+      ),
+      onTap: () {
+        // Tap row opens edit form
+        context.go('/rooms/${task.roomId}/tasks/${task.id}');
+      },
+      onLongPress: onDelete,
+    );
+  }
+}