Feat: 实现知识图谱数据库的检索方法，并对外提供接口

backend/handlers/search_handler.go

@@ -8,12 +8,12 @@ import (
 )
 
 type SearchHandler struct {
-	dataService *services.DataService
+	service services.GraphService
 }
 
-func NewSearchHandler(dataService *services.DataService) *SearchHandler {
+func NewSearchHandler(service services.GraphService) *SearchHandler {
 	return &SearchHandler{
-		dataService: dataService,
+		service: service,
 	}
 }
 
@@ -27,7 +27,7 @@ func (h *SearchHandler) SearchNodes(c *gin.Context) {
 		return
 	}
 
-	results := h.dataService.SearchNodes(query)
+	results := h.service.SearchNodes(query)
 
 	c.JSON(http.StatusOK, results)
 }