feat(14-01): add site_id device filter, wireless data endpoints, and frontend API clients
- Add site_id and sector_id query parameters to devices list endpoint
- Add get_device_registrations and get_device_rf_stats to link_service
- Add RegistrationResponse, RFStatsResponse schemas to link.py
- Add /registrations and /rf-stats endpoints to links router
- Add sectorsApi frontend client (list, create, update, delete, assignDevice)
- Add wirelessApi frontend client (links, registrations, RF stats, unknown clients)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>