- calendarDayProvider watches sortPreferenceProvider and sorts dayTasks
- overdueTasks intentionally unsorted (pinned at top per design decision)
- tasksInRoomProvider watches sortPreferenceProvider and sorts via stream.map
- _sortTasks helper (TaskWithRoom) and _sortTasksRaw helper (Task) both support:
- alphabetical: case-insensitive A-Z by name
- interval: by intervalType.index ascending, intervalDays as tiebreaker
- effort: by effortLevel.index ascending (low→medium→high)
- All 113 tests pass, analyze clean
- 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
