feat(frontend): add Helm chart browser, monitoring, chart-references and values templates pages

Add new frontend pages for the multi-tenant OCDP platform:

- Charts page (/charts): Browse Harbor OCI registries to list Helm chart repositories
  and versions, with deploy modal to launch charts on selected clusters
- Monitoring page (/monitoring): Display cluster metrics (CPU/Memory/GPU usage)
  and per-node details with resource utilization bars
- Chart References page (/chart-references): CRUD for chart metadata references
- Values Templates page (/templates): CRUD for Helm values templates with version
  history and rollback support
- Sidebar: Add Charts navigation, update Storage and Templates links
- api.ts: Add all API client functions (clusterApi, registryApi, instanceApi,
  monitoringApi, storageApi, chartReferenceApi, valuesTemplateApi,
  workspaceApi, userApi) with full TypeScript types

Note: deploy flow and values template rollback not yet end-to-end tested.

backend/internal/domain/service/registry_service.go

@@ -2,6 +2,8 @@ package service
 
 import (
 	"context"
+	"os"
+
 	"github.com/google/uuid"
 	"github.com/ocdp/cluster-service/internal/domain/entity"
 	"github.com/ocdp/cluster-service/internal/domain/repository"
@@ -40,6 +42,13 @@ func (s *RegistryService) CreateRegistry(ctx context.Context, registry *entity.R
 		return entity.ErrRegistryExists
 	}
 
+	// 非 mock 模式下验证连接
+	if os.Getenv("ADAPTER_MODE") != "mock" {
+		if err := s.ociClient.CheckHealth(ctx, registry); err != nil {
+			return err
+		}
+	}
+
 	return s.registryRepo.Create(ctx, registry)
 }