Add Done button, tablet controls, super admin management, midnight strike reset, and activity log improvements

- Done button snaps block to full duration, marks complete, logs "Marked Done by User"; Reset after Done fully un-completes the block
- Session action buttons stretch full-width and double height for tablet tapping
- Super admin: reset password, disable/enable accounts, delete user (with cascade), last active date per user's timezone
- Disabled account login returns specific error message instead of generic invalid credentials
- Users can change own password from Admin → Settings
- Strikes reset automatically at midnight in user's configured timezone (lazy reset on page load)
- Break timer state fully restored when navigating away and back to dashboard
- Timer no longer auto-starts on navigation if it wasn't running before
- Implicit pause guard: no duplicate pause events when switching already-paused blocks or starting a break
- Block selection events removed from activity log; all event types have human-readable labels
- House emoji favicon via inline SVG data URI
- README updated to reflect all changes

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

backend/app/routers/dashboard.py

@@ -17,7 +17,7 @@ from app.models.schedule import ScheduleBlock
 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
-from app.utils.timer import compute_block_elapsed
+from app.utils.timer import compute_block_elapsed, compute_break_elapsed
 
 router = APIRouter(prefix="/api/dashboard", tags=["dashboard"])
 
@@ -65,10 +65,34 @@ async def get_dashboard(child_id: int, db: AsyncSession = Depends(get_db)):
 
     # Compute elapsed seconds and paused state for the current block from timer_events
     is_paused = False
+    is_break_active = False
+    break_elapsed_seconds = 0
+    is_break_paused = False
     if session and session.current_block_id:
         block_elapsed_seconds, is_paused = await compute_block_elapsed(
             db, session.id, session.current_block_id
         )
+        # Determine if break mode is active: check whether the most recent
+        # timer event for this block (main or break) is a break event.
+        last_event_result = await db.execute(
+            select(TimerEvent)
+            .where(
+                TimerEvent.session_id == session.id,
+                TimerEvent.block_id == session.current_block_id,
+                TimerEvent.event_type.in_([
+                    "start", "resume",
+                    "break_start", "break_resume", "break_pause", "break_reset",
+                ]),
+            )
+            .order_by(TimerEvent.occurred_at.desc())
+            .limit(1)
+        )
+        last_event = last_event_result.scalar_one_or_none()
+        if last_event and last_event.event_type.startswith("break_"):
+            is_break_active = True
+            break_elapsed_seconds, is_break_paused = await compute_break_elapsed(
+                db, session.id, session.current_block_id
+            )
 
     routine_result = await db.execute(
         select(MorningRoutineItem)
@@ -93,4 +117,7 @@ async def get_dashboard(child_id: int, db: AsyncSession = Depends(get_db)):
         is_paused=is_paused,
         morning_routine=morning_routine,
         break_activities=break_activities,
+        is_break_active=is_break_active,
+        break_elapsed_seconds=break_elapsed_seconds,
+        is_break_paused=is_break_paused,
     )