fix: code 0 is success

cmd/api/main.go

@@ -21,7 +21,7 @@ func main() {
 
 	r.Get("/", func(w http.ResponseWriter, r *http.Request) {
 		render.JSON(w, r, map[string]interface{}{
-			"code":    http.StatusOK,
+			"code":    0,
 			"message": "Hello World",
 			"data":    struct{}{},
 		})