fix(nuxt): tidy up remnants of previous useId implementation

docs/3.api/2.composables/use-id.md

@@ -1,42 +0,0 @@
----
-title: "useId"
-description: Generate an SSR-friendly unique identifier that can be passed to accessibility attributes.
-links:
-  - label: Source
-    icon: i-simple-icons-github
-    to: https://github.com/nuxt/nuxt/blob/main/packages/nuxt/src/app/composables/id.ts
-    size: xs
----
-
-::important
-This composable is available since [Nuxt v3.10](/blog/v3-10#ssr-safe-accessible-unique-id-creation).
-::
-
-`useId` generates an SSR-friendly unique identifier that can be passed to accessibility attributes.
-
-Call `useId` at the top level of your component to generate a unique string identifier:
-
-```vue [components/EmailField.vue]
-<script setup lang="ts">
-const id = useId()
-</script>
-
-<template>
-  <div>
-    <label :for="id">Email</label>
-    <input :id="id" name="email" type="email" />
-  </div>
-</template>
-```
-
-::note
-`useId` must be used in a component with a single root element, as it uses this root element's attributes to pass the id from server to client.
-::
-
-## Parameters
-
-`useId` does not take any parameters.
-
-## Returns
-
-`useId` returns a unique string associated with this particular `useId` call in this particular component.

packages/nuxt/src/app/composables/id.ts

@@ -1,3 +1,4 @@
 import { useId as _useId } from 'vue'
 
+/** @deprecated Use `useId` from `vue` */
 export const useId = _useId

packages/nuxt/src/app/nuxt.ts

@@ -114,11 +114,6 @@ interface _NuxtApp {
    * The id of the Nuxt application.
    * @internal */
   _id: string
-  /**
-   * The next id that can be used for generating unique ids via `useId`.
-   * @internal
-   */
-  _genId?: number
   /** @internal */
   _scope: EffectScope
   /** @internal */