- Add modifiedFiles and baseCommitSha fields to task schema for tracking changes
- Capture list of modified files during task execution in the executor
- Add GET /tasks/:id/diff API endpoint to retrieve file list and patches
- Create TaskChangesTab component with expandable file diffs
- Integrate Changes tab into TaskDetailModal for in-progress, in-review, and done tasks
- Add CSS styles for diff viewer with syntax highlighting
- Update API client with fetchTaskDiff function and Project Management types