- Replace raw fetch() with apiPost/apiPatch/apiDelete in:
- ImportExportActions.tsx: POST for file imports
- KanbanBoard.tsx: PATCH for task status updates
- ActiveProjectsWidget.tsx: POST for widget data fetches
- useLayouts.ts: POST/PATCH/DELETE for layout management
- Add apiPostFormData() method to API client for FormData uploads
- Ensures CSRF token is included in all state-changing requests
- Update tests to mock CSRF token fetch for API client usage
Refs #338
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>