feat(admin): 分组管理新增容量列（并发/会话/RPM 实时聚合）

复用 GroupCapacityService，在 admin 分组列表中添加容量列，
显示每个分组的实时并发/会话/RPM 使用量和上限。

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/internal/handler/admin/admin_basic_handlers_test.go

@@ -17,8 +17,8 @@ func setupAdminRouter() (*gin.Engine, *stubAdminService) {
 	adminSvc := newStubAdminService()
 
 	userHandler := NewUserHandler(adminSvc, nil)
-	groupHandler := NewGroupHandler(adminSvc, nil)
-	proxyHandler := NewProxyHandler(adminSvc, nil, nil)
+	groupHandler := NewGroupHandler(adminSvc, nil, nil)
+	proxyHandler := NewProxyHandler(adminSvc)
 	redeemHandler := NewRedeemHandler(adminSvc, nil)
 
 	router.GET("/api/v1/admin/users", userHandler.List)

backend/internal/handler/admin/group_handler.go

@@ -17,8 +17,9 @@ import (
 
 // GroupHandler handles admin group management
 type GroupHandler struct {
-	adminService     service.AdminService
-	dashboardService *service.DashboardService
+	adminService         service.AdminService
+	dashboardService     *service.DashboardService
+	groupCapacityService *service.GroupCapacityService
 }
 
 type optionalLimitField struct {
@@ -71,10 +72,11 @@ func (f optionalLimitField) ToServiceInput() *float64 {
 }
 
 // NewGroupHandler creates a new admin group handler
-func NewGroupHandler(adminService service.AdminService, dashboardService *service.DashboardService) *GroupHandler {
+func NewGroupHandler(adminService service.AdminService, dashboardService *service.DashboardService, groupCapacityService *service.GroupCapacityService) *GroupHandler {
 	return &GroupHandler{
-		adminService:     adminService,
-		dashboardService: dashboardService,
+		adminService:         adminService,
+		dashboardService:     dashboardService,
+		groupCapacityService: groupCapacityService,
 	}
 }
 
@@ -382,6 +384,17 @@ func (h *GroupHandler) GetUsageSummary(c *gin.Context) {
 	response.Success(c, results)
 }
 
+// GetCapacitySummary returns aggregated capacity (concurrency/sessions/RPM) for all active groups.
+// GET /api/v1/admin/groups/capacity-summary
+func (h *GroupHandler) GetCapacitySummary(c *gin.Context) {
+	results, err := h.groupCapacityService.GetAllGroupCapacity(c.Request.Context())
+	if err != nil {
+		response.Error(c, 500, "Failed to get group capacity summary")
+		return
+	}
+	response.Success(c, results)
+}
+
 // GetGroupAPIKeys handles getting API keys in a group
 // GET /api/v1/admin/groups/:id/api-keys
 func (h *GroupHandler) GetGroupAPIKeys(c *gin.Context) {

backend/internal/handler/dto/mappers.go

@@ -135,16 +135,16 @@ func GroupFromServiceAdmin(g *service.Group) *AdminGroup {
 		return nil
 	}
 	out := &AdminGroup{
-		Group:                groupFromServiceBase(g),
-		ModelRouting:         g.ModelRouting,
-		ModelRoutingEnabled:  g.ModelRoutingEnabled,
-		MCPXMLInject:         g.MCPXMLInject,
-		DefaultMappedModel:   g.DefaultMappedModel,
-		SupportedModelScopes: g.SupportedModelScopes,
+		Group:                   groupFromServiceBase(g),
+		ModelRouting:            g.ModelRouting,
+		ModelRoutingEnabled:     g.ModelRoutingEnabled,
+		MCPXMLInject:            g.MCPXMLInject,
+		DefaultMappedModel:      g.DefaultMappedModel,
+		SupportedModelScopes:    g.SupportedModelScopes,
 		AccountCount:            g.AccountCount,
 		ActiveAccountCount:      g.ActiveAccountCount,
 		RateLimitedAccountCount: g.RateLimitedAccountCount,
-		SortOrder:            g.SortOrder,
+		SortOrder:               g.SortOrder,
 	}
 	if len(g.AccountGroups) > 0 {
 		out.AccountGroups = make([]AccountGroup, 0, len(g.AccountGroups))

backend/internal/handler/dto/types.go

@@ -122,8 +122,8 @@ type AdminGroup struct {
 	DefaultMappedModel string `json:"default_mapped_model"`
 
 	// 支持的模型系列（仅 antigravity 平台使用）
-	SupportedModelScopes []string       `json:"supported_model_scopes"`
-	AccountGroups        []AccountGroup `json:"account_groups,omitempty"`
+	SupportedModelScopes    []string       `json:"supported_model_scopes"`
+	AccountGroups           []AccountGroup `json:"account_groups,omitempty"`
 	AccountCount            int64          `json:"account_count,omitempty"`
 	ActiveAccountCount      int64          `json:"active_account_count,omitempty"`
 	RateLimitedAccountCount int64          `json:"rate_limited_account_count,omitempty"`

backend/internal/handler/sora_gateway_handler_test.go

@@ -348,6 +348,9 @@ func (s *stubUsageLogRepo) GetGroupStatsWithFilters(ctx context.Context, startTi
 func (s *stubUsageLogRepo) GetUserBreakdownStats(ctx context.Context, startTime, endTime time.Time, dim usagestats.UserBreakdownDimension, limit int) ([]usagestats.UserBreakdownItem, error) {
 	return nil, nil
 }
+func (s *stubUsageLogRepo) GetAllGroupUsageSummary(ctx context.Context, todayStart time.Time) ([]usagestats.GroupUsageSummary, error) {
+	return nil, nil
+}
 func (s *stubUsageLogRepo) GetAPIKeyUsageTrend(ctx context.Context, startTime, endTime time.Time, granularity string, limit int) ([]usagestats.APIKeyUsageTrendPoint, error) {
 	return nil, nil
 }