fix: fix wrong export of subscription type

Author: Pascal Klesse

src/runtime/composables/gql-subscription.ts

@@ -1,20 +1,13 @@
 import { subscription } from 'gql-query-builder';
 import gql from 'graphql-tag';
 import { useNuxtApp } from 'nuxt/app';
-import { type Ref, ref } from 'vue';
+import { ref } from 'vue';
 
 import type { IGraphQLOptions } from '../interfaces/graphql-options.interface';
+import type { ReturnTypeOfSubscription } from '../interfaces/return-type-of-subscription.interface';
 
 import { hashPasswords } from '../functions/graphql-meta';
 
-export interface ReturnTypeOfSubscription<T> {
-  data: Ref<T>;
-  error: Ref<string>;
-  loading: Ref<boolean>;
-  start: void;
-  stop: void;
-}
-
 export async function gqlSubscription<T = any>(method: string, options: IGraphQLOptions = {}): Promise<ReturnTypeOfSubscription<T>> {
   const { _meta, _wsClient } = useNuxtApp();
 

src/runtime/interfaces/return-type-of-subscription.interface.ts

@@ -0,0 +1,9 @@
+import type { Ref } from 'vue';
+
+export interface ReturnTypeOfSubscription<T> {
+  data: Ref<T | null>;
+  error: Ref<null | string>;
+  loading: Ref<boolean>;
+  start: () => void;
+  stop: () => void;
+}