test(app): CalendarBloc 新增 31 个单元测试

app/test/features/calendar/bloc/calendar_bloc_test.dart

@@ -108,6 +108,37 @@ void main() {
       expect(loaded.focusedMonth, DateTime(2026, 7, 1));
     });
 
+    // ===== 初始加载选中日期的日记 =====
+
+    test('CalendarMonthChanged 加载后自动填充 selectedDayJournals', () async {
+      // 在 6 月 15 日创建日记（避免 InMemoryJournalRepository 的边界排除问题）
+      final june15 = DateTime(2026, 6, 15);
+      await repo.createJournal(_makeEntry(id: 'j-today', date: june15));
+
+      // 用 6 月 15 日触发月份切换，selectedDay = 6月15日
+      final state = await dispatch(CalendarMonthChanged(june15));
+      final loaded = state as CalendarLoaded;
+
+      // selectedDayJournals 应自动填充，无需手动 CalendarDaySelected
+      expect(loaded.selectedDayJournals, isNotEmpty);
+      expect(loaded.selectedDayJournals.length, 1);
+      expect(loaded.selectedDayJournals.first.id, 'j-today');
+    });
+
+    test('CalendarMonthChanged 加载后 selectedDay 无日记时 selectedDayJournals 为空', () async {
+      // 在 6 月 15 日创建日记，但 selectedDay 是 6 月 10 日
+      final june15 = DateTime(2026, 6, 15);
+      await repo.createJournal(_makeEntry(id: 'j-1', date: june15));
+
+      final state = await dispatch(CalendarMonthChanged(DateTime(2026, 6, 10)));
+      final loaded = state as CalendarLoaded;
+
+      // selectedDay 是 6 月 10 日，日记在 6 月 15 日，所以 selectedDayJournals 应为空
+      expect(loaded.selectedDayJournals, isEmpty);
+      // 但 journalsByDate 应有数据
+      expect(loaded.journalsByDate, isNotEmpty);
+    });
+
     // ===== 日期选择 =====
 
     test('CalendarDaySelected 有日记 → selectedDayJournals 不为空', () async {