feat: fix YAML field conversion, admin namespace, streaming logs, and vllm-serve deploy

- Fix Axios keysToSnake converting user values map keys (gpuMem -> gpu_mem)
  - Add skipRecurseKeys to keysToSnake for values/valuesYaml fields
  - Add values_yaml alt json tag and Normalize() in DTOs
  - Check both camelCase/snake_case in enforceNamespaceValues
  - Read both tailLines/tail_lines query param for diagnostics
- Admin users can freely choose namespace in LaunchModal (free-text input)
  - Block only kube-system/kube-public/kube-node-lease for admin
  - Regular users keep existing namespace restrictions
- Add SSE streaming pod logs endpoint (backend + frontend)
  - New PodLogStreamer interface and K8s Follow:true implementation
  - SSE handler with text/event-stream output
  - Frontend DiagnosticsModal: Stream button, auto-scroll, live indicator
- Remove per-card Refresh button from InstanceCard (redundant with page refresh)
- Deploy bge-m3 on vllm-serve 0.6.0 (gpuMem=10000, status=deployed)

backend/cmd/api/main.go

@@ -284,6 +284,7 @@ func setupRouter(
 	protected.HandleFunc("/clusters/{cluster_id}/instances/{instance_id}", instanceHandler.DeleteInstance).Methods(http.MethodDelete)
 	protected.HandleFunc("/clusters/{cluster_id}/instances/{instance_id}/entries", instanceHandler.ListInstanceEntries).Methods(http.MethodGet)
 	protected.HandleFunc("/clusters/{cluster_id}/instances/{instance_id}/diagnostics", instanceHandler.GetInstanceDiagnostics).Methods(http.MethodGet)
+	protected.HandleFunc("/clusters/{cluster_id}/instances/{instance_id}/logs/stream", instanceHandler.StreamInstanceLogs).Methods(http.MethodGet)
 
 	// ===== Monitoring 路由 =====
 	protected.HandleFunc("/monitoring/clusters", monitoringHandler.ListClusterMonitoring).Methods(http.MethodGet)