95f2b1d4a1
Introduces a `useTimer` hook to manage starting and stopping timers for tasks, updating their `timeTracked` property, and displaying tracking status. This involves changes in `App.tsx`, `KanbanBoard.tsx`, `TaskCard.tsx`, and `TasksWithCalendar.tsx` to integrate the timer start/stop actions and display. Replit-Commit-Author: Agent Replit-Commit-Session-Id: ceced2fc-aa46-458d-ba87-ddd4b7bb1518 Replit-Commit-Checkpoint-Type: intermediate_checkpoint Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/659922a9-0087-461c-90dd-6d9a58b81d4d/ceced2fc-aa46-458d-ba87-ddd4b7bb1518/P2PZNJ9