Add subject options and redesign TV dashboard layout

Subject options:
- New subject_options table (auto-created on startup)
- SubjectOut now includes options list; all eager-loading chains updated
- Admin: Options panel per subject with add, inline edit, and delete
- WS broadcast and dashboard API include options in block subject data

TV dashboard:
- Three equal columns: Timer | Activities | Schedule
- Activities column shows current subject's options in large readable text
- Activities area has subject-colored border and tinted background
- Subject name and label displayed correctly using embedded subject data

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

backend/app/routers/dashboard.py

@@ -12,6 +12,7 @@ from sqlalchemy.orm import selectinload
 from app.dependencies import get_db
 from app.models.child import Child
 from app.models.schedule import ScheduleBlock, ScheduleTemplate
+from app.models.subject import Subject  # noqa: F401 — needed for selectinload chain
 from app.models.session import DailySession, TimerEvent
 from app.schemas.session import DashboardSnapshot
 
@@ -48,6 +49,7 @@ async def get_dashboard(child_id: int, db: AsyncSession = Depends(get_db)):
         blocks_result = await db.execute(
             select(ScheduleBlock)
             .where(ScheduleBlock.template_id == session.template_id)
+            .options(selectinload(ScheduleBlock.subject).selectinload(Subject.options))
             .order_by(ScheduleBlock.order_index)
         )
         blocks = blocks_result.scalars().all()