Add Morning Routine to Admin and TV greeting state

Adds a per-user Morning Routine item list that appears in the TV
dashboard Activities panel during the "Good Morning" countdown
(before the first block starts).

- morning_routine_items table (auto-created on startup)
- CRUD API at /api/morning-routine (auth-required)
- Items included in the public DashboardSnapshot so TV gets them
  without auth
- Morning Routine section in Admin page (same add/edit/delete UX
  as subject options)
- TV Activities column shows routine items when no block is active,
  switches to subject options once a block starts

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

backend/app/main.py

@@ -9,6 +9,7 @@ from app.config import get_settings
 from app.database import engine
 from app.models import Base
 from app.routers import auth, users, children, subjects, schedules, sessions, logs, dashboard
+from app.routers import morning_routine
 from app.websocket.manager import manager
 
 settings = get_settings()
@@ -62,6 +63,7 @@ app.include_router(subjects.router)
 app.include_router(schedules.router)
 app.include_router(sessions.router)
 app.include_router(logs.router)
+app.include_router(morning_routine.router)
 app.include_router(dashboard.router)