fix: seed partial overlap timeline tasks

apps/focus_flow_flutter/lib/app/demo_scheduler_composition.dart

@@ -229,6 +229,48 @@ class DemoSchedulerComposition {
         completedAt: _instant(date, 16, 20),
         createdAt: createdAt,
       ),
+      _task(
+        id: 'sort-mail',
+        title: 'Sort mail',
+        type: TaskType.flexible,
+        status: TaskStatus.planned,
+        date: date,
+        startHour: 14,
+        startMinute: 40,
+        endHour: 15,
+        endMinute: 20,
+        reward: RewardLevel.low,
+        difficulty: DifficultyLevel.easy,
+        createdAt: createdAt,
+      ),
+      _task(
+        id: 'start-laundry',
+        title: 'Start laundry',
+        type: TaskType.flexible,
+        status: TaskStatus.planned,
+        date: date,
+        startHour: 15,
+        startMinute: 0,
+        endHour: 15,
+        endMinute: 40,
+        reward: RewardLevel.medium,
+        difficulty: DifficultyLevel.medium,
+        createdAt: createdAt,
+      ),
+      _task(
+        id: 'water-plants',
+        title: 'Water plants',
+        type: TaskType.flexible,
+        status: TaskStatus.planned,
+        date: date,
+        startHour: 15,
+        startMinute: 20,
+        endHour: 16,
+        endMinute: 0,
+        reward: RewardLevel.medium,
+        difficulty: DifficultyLevel.medium,
+        createdAt: createdAt,
+      ),
       _task(
         id: 'pay-bill',
         title: 'Pay bill',

apps/focus_flow_flutter/test/widget_test.dart

@@ -44,6 +44,9 @@ void main() {
     );
     expect(find.text('Clean coffee maker'), findsOneWidget);
     expect(find.text('Cleaned kitchen counter'), findsNWidgets(2));
+    expect(find.text('Sort mail'), findsOneWidget);
+    expect(find.text('Start laundry'), findsOneWidget);
+    expect(find.text('Water plants'), findsOneWidget);
     expect(find.text('Pay bill'), findsOneWidget);
     expect(find.text('Doctor appointment'), findsOneWidget);
     expect(find.text('Free Slot'), findsOneWidget);
@@ -57,6 +60,9 @@ void main() {
       final data = TodayScreenData.fromTodayState(state);
 
       expect(_kindFor(data, 'clean-coffee-maker'), TaskVisualKind.flexible);
+      expect(_kindFor(data, 'sort-mail'), TaskVisualKind.flexible);
+      expect(_kindFor(data, 'start-laundry'), TaskVisualKind.flexible);
+      expect(_kindFor(data, 'water-plants'), TaskVisualKind.flexible);
       expect(_kindFor(data, 'pay-bill'), TaskVisualKind.required);
       expect(_kindFor(data, 'doctor-appointment'), TaskVisualKind.appointment);
       expect(_kindFor(data, 'free-slot'), TaskVisualKind.freeSlot);
@@ -159,7 +165,7 @@ void main() {
     },
   );
 
-  testWidgets('timeline reuses empty overlap lanes for chained tasks', (
+  testWidgets('timeline splits partial overlaps and reuses empty lanes', (
     tester,
   ) async {
     await _pumpConstrainedWidget(
@@ -210,6 +216,41 @@ void main() {
     expect(leftReused.right, lessThan(rightMiddle.left));
   });
 
+  testWidgets('seeded demo partial overlaps pack into two lanes', (
+    tester,
+  ) async {
+    final state = await _readSeededToday();
+    final data = TodayScreenData.fromTodayState(state);
+
+    await _pumpConstrainedWidget(
+      tester,
+      size: const Size(900, 620),
+      child: TimelineView(
+        cards: data.cards,
+        range: data.timelineRange,
+        now: () => DateTime(2025, 5, 20, 15, 20),
+        onCardSelected: (_) {},
+      ),
+    );
+
+    expect(tester.takeException(), isNull);
+
+    final sortMail = tester.getRect(find.byKey(const ValueKey('sort-mail')));
+    final startLaundry = tester.getRect(
+      find.byKey(const ValueKey('start-laundry')),
+    );
+    final waterPlants = tester.getRect(
+      find.byKey(const ValueKey('water-plants')),
+    );
+
+    expect(startLaundry.left, greaterThan(sortMail.left));
+    expect(waterPlants.left, closeTo(sortMail.left, 1));
+    expect(sortMail.width, closeTo(startLaundry.width, 1));
+    expect(waterPlants.width, closeTo(sortMail.width, 1));
+    expect(sortMail.right, lessThan(startLaundry.left));
+    expect(waterPlants.right, lessThan(startLaundry.left));
+  });
+
   testWidgets('top bar controls scale inside a compact header width', (
     tester,
   ) async {