feat(api): add dashboard summary and system realtime endpoints

Add new admin API endpoints for dashboard metrics and system-wide
realtime statistics:

- Add /admin/dashboard/summary endpoint with aggregated metrics
  including requests, tokens, latency, masters, keys, and provider
  keys statistics with time period filtering
- Add /admin/realtime endpoint for system-level realtime stats
  aggregated across all masters
- Add status filter parameter to ListAPIKeys endpoint
- Add hour grouping option to log stats aggregation
- Update OpenAPI documentation with new endpoints and schemas

internal/api/api_key_handler.go

@@ -92,13 +92,14 @@ func (h *Handler) CreateAPIKey(c *gin.Context) {
 
 // ListAPIKeys godoc
 // @Summary      List API keys
-// @Description  List API keys
+// @Description  List API keys with optional filters
 // @Tags         admin
 // @Produce      json
 // @Security     AdminAuth
-// @Param        page     query     int   false  "page (1-based)"
-// @Param        limit    query     int   false  "limit (default 50, max 200)"
-// @Param        group_id query     int   false  "filter by group_id"
+// @Param        page     query     int     false  "page (1-based)"
+// @Param        limit    query     int     false  "limit (default 50, max 200)"
+// @Param        group_id query     int     false  "filter by group_id"
+// @Param        status   query     string  false  "filter by status (active, suspended, auto_disabled, manual_disabled)"
 // @Success      200      {array}   model.APIKey
 // @Failure      500      {object}  gin.H
 // @Router       /admin/api-keys [get]
@@ -108,6 +109,9 @@ func (h *Handler) ListAPIKeys(c *gin.Context) {
 	if groupID := strings.TrimSpace(c.Query("group_id")); groupID != "" {
 		q = q.Where("group_id = ?", groupID)
 	}
+	if status := strings.TrimSpace(c.Query("status")); status != "" {
+		q = q.Where("status = ?", status)
+	}
 	query := parseListQuery(c)
 	q = applyListPagination(q, query)
 	if err := q.Find(&keys).Error; err != nil {