refactor(router): remove duplicate progress routes, add ProgressService to config

- Remove GET /progress/:id and POST /progress/:id from progress routes.
  These were superseded by the media-item progress routes. Only
  GET /progress/:id/history remains.

- Add ProgressService to router.Config so sync.go can inject it into
  KoboHandler via SetProgressService().

- Inject ProgressService into KoboHandler at route registration time
  rather than requiring a separate setup step.

- Update comment from 'Legacy progress routes' to 'Progress routes'.

internal/router/router.go

@@ -60,6 +60,7 @@ type Config struct {
 	SystemSettingsHandler   *handlers.SystemSettingsHandler
 	ConnManager             *sync.ConnectionManager
 	QueueProcessor          *sync.SyncQueueProcessor
+	ProgressService         *sync.ProgressService
 	DeviceAuthMiddleware    *middleware.DeviceAuthMiddleware
 	LoginTracker            *ratelimit.LoginAttemptTracker
 	ScannerHandler          *handlers.Handler