- Update TaskCard and TaskDetailModal to display description as fallback instead of repeating the task ID
- Remove unused hooks (useFlashOnIncrease), routes, assets, and dead CSS
- Clean up engine modules (executor, scheduler, triage, worktree-names) removing unused code
- Update and add tests for title fallback behavior in TaskDetailModal
- Fix pre-existing type error in test helper (types.ts)
- Set task status to 'failed' on execution failure in engine executor
- Add failed indicator styling on TaskCard component
- Add POST /tasks/:id/retry API endpoint and client function
- Add retry button in TaskDetailModal for failed tasks
- Add tests for failed indicator, retry endpoint, and modal behavior
- Fix prompt heading to use only task ID when title is absent, preventing description duplication
- Strip leading markdown heading from TaskDetailModal since the modal has its own header
- Add store tests covering prompt generation for tasks with and without titles
- Update TaskDetailModal tests to verify heading stripping and single description rendering
