refactor: enhance TimerPage layout and functionality; update theme and tokens for improved design consistency

- Refactored TimerPage component to improve layout and user experience.
- Updated theme configuration to utilize design tokens for better maintainability.
- Introduced new tokens for colors and typography to align with design principles.
- Simplified state management and improved timer functionality.
- Enhanced accessibility and responsiveness of UI elements.

backend/app/api/routes_tasks.py

@@ -1,11 +1,15 @@
-"""Task endpoints: the aggregated list, refreshing it, and acting on it."""
+"""Task endpoints: the aggregated list and the refresh that keeps it honest.
+
+There is no "mark done" here on purpose — a task is closed where it lives, and
+the refresh notices. See `app.services.tasks_service`.
+"""
 
 from __future__ import annotations
 
 from fastapi import APIRouter, HTTPException, Query
 
 from app.api.deps import DbSession, Settings
-from app.api.schemas import TaskCreateRequest, TaskDoneRequest, TaskUpdateRequest
+from app.api.schemas import TaskCreateRequest, TaskUpdateRequest
 from app.models import TaskRecord
 from app.services import tasks_service
 from app.sources.registry import SOURCE_LABELS, check_source
@@ -40,12 +44,15 @@ def task_dict(record: TaskRecord, today) -> dict:
 
 
 def _bucket_of(record: TaskRecord, today) -> str:
-    if record.due_date is None:
-        return "someday"
-    if record.due_date < today:
+    if record.due_date is not None and record.due_date < today:
         return "overdue"
     if record.due_date == today:
         return "today"
+    if record.start_date is not None and record.start_date <= today:
+        # Started, but not due today — in progress rather than "upcoming".
+        return "active"
+    if record.due_date is None:
+        return "someday"
     return "upcoming"
 
 
@@ -99,15 +106,6 @@ def update(task_id: int, body: TaskUpdateRequest, session: DbSession, settings:
     return task_dict(record, local_date(settings.timezone))
 
 
-@router.post("/{task_id}/done")
-def mark_done(task_id: int, body: TaskDoneRequest, session: DbSession, settings: Settings) -> dict:
-    try:
-        record, warning = tasks_service.complete_task(session, settings, task_id, done=body.done)
-    except LookupError as exc:
-        raise HTTPException(status_code=404, detail=str(exc)) from exc
-    return {"task": task_dict(record, local_date(settings.timezone)), "warning": warning}
-
-
 @router.delete("/{task_id}")
 def delete(task_id: int, session: DbSession) -> dict:
     tasks_service.delete_task(session, task_id)