Introduce staff reliability statistics and location fields across domain, data, and UI. Changes include:
- New API endpoint StaffEndpoints.profileStats ('/staff/profile/stats').
- New domain entity StaffReliabilityStats with JSON (de)serialization and export.
- Profile repository: getReliabilityStats implementation and interface addition.
- New GetReliabilityStatsUseCase and DI registration in StaffProfileModule.
- ProfileCubit/state: load and store reliabilityStats; UI wired to display ReliabilityStatsCard and ReliabilityScoreBar using state values.
- Coverage/shift updates: Added AssignedWorker.hasReview to track if a worker was reviewed; added locationName/locationAddress to ShiftWithWorkers and show location in ShiftHeader; hide rate button if worker.hasReview.
- Clock-in handling: treat backend ALREADY_CLOCKED_IN (409) as idempotent by re-fetching attendance and emitting success when appropriate.
These changes wire backend stats through repository/usecase/cubit to the profile UI and add shift location and review-awareness to client views.