feat(05-02): build CalendarStrip, CalendarTaskRow, CalendarDayList widgets

- Add totalTaskCount field to CalendarDayState to distinguish first-run from celebration
- Add getTaskCount() to CalendarDao (SELECT COUNT from tasks)
- CalendarStrip: 181-day horizontal scroll with German abbreviations, today highlighting, month boundary labels, scroll-to-today controller
- CalendarTaskRow: task name + room tag chip + checkbox, no relative date, isOverdue coral styling
- CalendarDayList: loading/error/first-run-empty/empty-day/celebration/has-tasks states, overdue section (today only), slide-out completion animation
- Update home_screen_test.dart and app_shell_test.dart to test new calendar providers instead of dailyPlanProvider

lib/features/home/presentation/calendar_task_row.dart

@@ -0,0 +1,69 @@
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+
+import 'package:household_keeper/features/home/domain/daily_plan_models.dart';
+
+/// Warm coral/terracotta color for overdue task name text.
+const _overdueColor = Color(0xFFE07A5F);
+
+/// A task row adapted for the calendar day list.
+///
+/// Shows task name, a tappable room tag (navigates to room task list),
+/// and an interactive checkbox. Does NOT show a relative date — the
+/// calendar strip already communicates which day is selected.
+///
+/// When [isOverdue] is true the task name uses coral text to visually
+/// distinguish overdue carry-over from today's regular tasks.
+class CalendarTaskRow extends StatelessWidget {
+  const CalendarTaskRow({
+    super.key,
+    required this.taskWithRoom,
+    required this.onCompleted,
+    this.isOverdue = false,
+  });
+
+  final TaskWithRoom taskWithRoom;
+
+  /// Called when the user checks the checkbox.
+  final VoidCallback onCompleted;
+
+  /// When true, task name is rendered in coral color.
+  final bool isOverdue;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final task = taskWithRoom.task;
+
+    return ListTile(
+      leading: Checkbox(
+        value: false,
+        onChanged: (_) => onCompleted(),
+      ),
+      title: Text(
+        task.name,
+        style: theme.textTheme.titleMedium?.copyWith(
+          color: isOverdue ? _overdueColor : null,
+        ),
+        maxLines: 1,
+        overflow: TextOverflow.ellipsis,
+      ),
+      subtitle: GestureDetector(
+        onTap: () => context.go('/rooms/${taskWithRoom.roomId}'),
+        child: Container(
+          padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 2),
+          decoration: BoxDecoration(
+            color: theme.colorScheme.secondaryContainer,
+            borderRadius: BorderRadius.circular(4),
+          ),
+          child: Text(
+            taskWithRoom.roomName,
+            style: theme.textTheme.labelSmall?.copyWith(
+              color: theme.colorScheme.onSecondaryContainer,
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}