feat: complete tag management and UI integration

- Marked multiple tasks as completed in TODO.md related to tag management features.
- Replaced manual tag input with `TagInput` component in `CreateTaskForm`, `EditTaskForm`, and `QuickAddTask` for better UX.
- Updated `TaskCard` to display tags using `TagDisplay` with color support.
- Enhanced `TasksService` to manage task-tag relationships with CRUD operations.
- Integrated tag management into the global context for better accessibility across components.

components/kanban/Board.tsx

@@ -118,6 +118,7 @@ export function KanbanBoard({ tasks, onCreateTask, onDeleteTask, onEditTask, onU
 
   return (
     <DndContext
+      id="kanban-board"
       sensors={sensors}
       onDragStart={handleDragStart}
       onDragEnd={handleDragEnd}