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/values_template_service.go

@@ -0,0 +1,143 @@
+package service
+
+import (
+	"context"
+	"errors"
+
+	"github.com/ocdp/cluster-service/internal/domain/entity"
+	"github.com/ocdp/cluster-service/internal/domain/repository"
+)
+
+var (
+	ErrTemplateNotFound = errors.New("template not found")
+	ErrTemplateExists   = errors.New("template already exists")
+)
+
+// ValuesTemplateService Values 模板领域服务
+type ValuesTemplateService struct {
+	valuesTemplateRepo repository.ValuesTemplateRepository
+	chartRefRepo       repository.ChartReferenceRepository
+}
+
+// NewValuesTemplateService 创建 Values 模板服务
+func NewValuesTemplateService(
+	valuesTemplateRepo repository.ValuesTemplateRepository,
+	chartRefRepo repository.ChartReferenceRepository,
+) *ValuesTemplateService {
+	return &ValuesTemplateService{
+		valuesTemplateRepo: valuesTemplateRepo,
+		chartRefRepo:       chartRefRepo,
+	}
+}
+
+// Create 创建 Values 模板
+func (s *ValuesTemplateService) Create(
+	ctx context.Context,
+	workspaceID, ownerID, chartRefID, name, description, valuesYAML string,
+	isDefault bool,
+) (*entity.ValuesTemplate, error) {
+	// 检查 Chart Reference 是否存在
+	chartRef, err := s.chartRefRepo.GetByID(ctx, chartRefID)
+	if err != nil {
+		return nil, errors.New("chart reference not found")
+	}
+
+	// 检查名称是否已存在
+	existing, _ := s.valuesTemplateRepo.GetByName(ctx, workspaceID, chartRefID, name)
+	if existing != nil {
+		return nil, ErrTemplateExists
+	}
+
+	template := entity.NewValuesTemplate(workspaceID, ownerID, chartRef.ID, name, valuesYAML)
+	template.Description = description
+	template.IsDefault = isDefault
+
+	if err := s.valuesTemplateRepo.Create(ctx, template); err != nil {
+		return nil, err
+	}
+
+	return template, nil
+}
+
+// GetByID 获取 Values 模板
+func (s *ValuesTemplateService) GetByID(ctx context.Context, id string) (*entity.ValuesTemplate, error) {
+	template, err := s.valuesTemplateRepo.GetByID(ctx, id)
+	if err != nil {
+		return nil, ErrTemplateNotFound
+	}
+	return template, nil
+}
+
+// GetByWorkspace 获取工作空间的所有 Values 模板
+func (s *ValuesTemplateService) GetByWorkspace(ctx context.Context, workspaceID string) ([]*entity.ValuesTemplate, error) {
+	return s.valuesTemplateRepo.GetByWorkspace(ctx, workspaceID)
+}
+
+// GetByChartReference 获取 Chart Reference 的所有 Values 模板
+func (s *ValuesTemplateService) GetByChartReference(ctx context.Context, chartRefID string) ([]*entity.ValuesTemplate, error) {
+	return s.valuesTemplateRepo.GetByChartReference(ctx, chartRefID)
+}
+
+// GetHistory 获取模板的版本历史
+func (s *ValuesTemplateService) GetHistory(ctx context.Context, chartRefID, name string) ([]*entity.ValuesTemplate, error) {
+	return s.valuesTemplateRepo.GetHistory(ctx, chartRefID, name)
+}
+
+// Update 更新 Values 模板（创建新版本）
+func (s *ValuesTemplateService) Update(
+	ctx context.Context,
+	id, description, valuesYAML string,
+	isDefault bool,
+) (*entity.ValuesTemplate, error) {
+	template, err := s.valuesTemplateRepo.GetByID(ctx, id)
+	if err != nil {
+		return nil, ErrTemplateNotFound
+	}
+
+	template.Description = description
+	template.ValuesYAML = valuesYAML
+	template.IsDefault = isDefault
+
+	if err := s.valuesTemplateRepo.Update(ctx, template); err != nil {
+		return nil, err
+	}
+
+	// 获取最新版本
+	return s.valuesTemplateRepo.GetByName(ctx, template.WorkspaceID, template.ChartReferenceID, template.Name)
+}
+
+// Delete 删除 Values 模板
+func (s *ValuesTemplateService) Delete(ctx context.Context, id string) error {
+	return s.valuesTemplateRepo.Delete(ctx, id)
+}
+
+// List 列出所有 Values 模板（管理员用）
+func (s *ValuesTemplateService) List(ctx context.Context) ([]*entity.ValuesTemplate, error) {
+	return s.valuesTemplateRepo.List(ctx)
+}
+
+// Rollback 回滚到指定版本
+func (s *ValuesTemplateService) Rollback(ctx context.Context, templateID string) (*entity.ValuesTemplate, error) {
+	// 获取历史版本模板
+	oldTemplate, err := s.valuesTemplateRepo.GetByID(ctx, templateID)
+	if err != nil {
+		return nil, ErrTemplateNotFound
+	}
+
+	// 重新创建该版本（创建新版本，内容与旧版本相同）
+	newTemplate := &entity.ValuesTemplate{
+		WorkspaceID:      oldTemplate.WorkspaceID,
+		OwnerID:          oldTemplate.OwnerID,
+		ChartReferenceID: oldTemplate.ChartReferenceID,
+		Name:             oldTemplate.Name,
+		Description:      oldTemplate.Description,
+		ValuesYAML:       oldTemplate.ValuesYAML,
+	}
+
+	if err := s.valuesTemplateRepo.Update(ctx, newTemplate); err != nil {
+		return nil, err
+	}
+
+	// 获取最新版本
+	return s.valuesTemplateRepo.GetByName(ctx, newTemplate.WorkspaceID, newTemplate.ChartReferenceID, newTemplate.Name)
+}