feat(server): integrate UDP video service and normalize database schema

- Implement UDPVideoService to stream MJPEG video frames from ESP32s via UDP and send control commands.
- Normalize race database schema:
  - Remove redundant driver_ids array from races table (migration 011).
  - Move per-driver outcomes (total_time_ms, best_lap_ms, position) to race_drivers table (migration 012).
  - Add device_id column to lobby_drivers to link active physical devices (migration 013).
- Update WebSocket handler to pass lobbySvc, driversSvc, and videoSvc for driver identity tracking, syncing in-memory driver metadata, and forwarding WS controls to physical cars.
- Add CORS middleware to HTTP routes.
- Regenerate Swagger documentation.

server/cmd/poc-server/races_handlers.go

@@ -85,7 +85,7 @@ func racesListHandler(svc *races.Service) http.HandlerFunc {
 		writeJSON(w, http.StatusOK, transport.RaceListResponse{
 			Items:      items,
 			NextCursor: res.NextCursor,
-			Count:      len(items),
+			Count:      res.TotalCount,
 		})
 	}
 }
@@ -382,10 +382,15 @@ func racePlansListHandler(svc *races.Service) http.HandlerFunc {
 			last := out[len(out)-1]
 			nextCur = races.Cursor{Ms: last.StartAtMs, ID: last.ID}.Encode()
 		}
+		totalCount, err := svc.CountPlans(r.Context())
+		if err != nil {
+			writeError(w, http.StatusInternalServerError, "internal", err.Error())
+			return
+		}
 		writeJSON(w, http.StatusOK, transport.RacePlanListResponse{
 			Items:      out,
 			NextCursor: nextCur,
-			Count:      len(out),
+			Count:      totalCount,
 		})
 	}
 }