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/adapter/input/http/dto/values_template_dto.go

@@ -0,0 +1,37 @@
+package dto
+
+// CreateValuesTemplateRequest 创建 Values 模板请求
+type CreateValuesTemplateRequest struct {
+	ChartReferenceID string `json:"chart_reference_id" binding:"required"`
+	Name             string `json:"name" binding:"required"`
+	Description      string `json:"description"`
+	ValuesYAML       string `json:"values_yaml" binding:"required"`
+	IsDefault        bool   `json:"is_default"`
+}
+
+// UpdateValuesTemplateRequest 更新 Values 模板请求
+type UpdateValuesTemplateRequest struct {
+	Description string `json:"description"`
+	ValuesYAML  string `json:"values_yaml"`
+	IsDefault   *bool  `json:"is_default"`
+}
+
+// ValuesTemplateResponse Values 模板响应
+type ValuesTemplateResponse struct {
+	ID                string `json:"id"`
+	WorkspaceID       string `json:"workspace_id,omitempty"`
+	OwnerID           string `json:"owner_id,omitempty"`
+	ChartReferenceID  string `json:"chart_reference_id"`
+	Name              string `json:"name"`
+	Description       string `json:"description"`
+	ValuesYAML        string `json:"values_yaml"`
+	Version           int    `json:"version"`
+	IsDefault         bool   `json:"is_default"`
+	CreatedAt         string `json:"createdAt"`
+	UpdatedAt         string `json:"updatedAt"`
+}
+
+// RollbackValuesTemplateRequest 回滚请求
+type RollbackValuesTemplateRequest struct {
+	TemplateID string `json:"template_id" binding:"required"`
+}