Move StaffApiMiddleware from the Controllers directory to the correct
Middleware directory to adhere to Laravel directory structure standards.
- Relocate StaffApiMiddleware from `app/Http/Controllers` to `app/Http/Middleware`
- Update `api.php` to use the correct namespace for `StaffApiMiddleware`
- Add `IFNEX_Logistics_Review_Workflow_HANDOFF.md` documentation for the review workflow
