fix: fix '' does not exist on type

src/extend.d.ts

@@ -1,12 +0,0 @@
-import { ComponentCustomProperties } from "vue";
-declare module "@vue/runtime-core" {
-  interface ComponentCustomProperties {
-    $message: typeof import("element-plus/es/components/message/src/message").ElMessage;
-    $notify: typeof import("element-plus/es/components/notification/src/notification").ElNotification;
-    $confirm: (typeof import("element-plus/es/components/message-box/src/message-box").ElMessageBox)["confirm"];
-    $alert: (typeof import("element-plus/es/components/message-box/src/message-box").ElMessageBox)["alert"];
-    $prompt: (typeof import("element-plus/es/components/message-box/src/message-box").ElMessageBox)["prompt"];
-  }
-}
-
-export default ComponentCustomProperties;

src/plugins/vue.d.ts

@@ -0,0 +1,10 @@
+declare module "vue" {
+  export interface ComponentCustomProperties {
+    $message: (typeof import("element-plus"))["ElMessage"];
+    $notify: (typeof import("element-plus"))["ElNotification"];
+    $confirm: (typeof import("element-plus"))["ElMessageBox"]["confirm"];
+    $alert: (typeof import("element-plus"))["ElMessageBox"]["alert"];
+    $prompt: (typeof import("element-plus"))["ElMessageBox"]["prompt"];
+  }
+}
+export type Size = "default" | "small" | "large";