fix: site form JS conflict with window.name

internal/handler/site.go

@@ -67,7 +67,7 @@ func (h *SiteHandler) Create(w http.ResponseWriter, r *http.Request) {
 			errors.Is(err, sitesvc.ErrInvalidPHPVersion):
 			writeError(w, http.StatusBadRequest, err.Error())
 		default:
-			writeError(w, http.StatusInternalServerError, "failed to create site")
+			writeError(w, http.StatusInternalServerError, "failed to create site: "+err.Error())
 		}
 		return
 	}