fix!: properly handle context when using multiple nuxt instances (#762)

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### 🔗 Linked issue

 This finally fixes #661.
<!-- If it resolves an open issue, please link the issue here. For
example "Resolves #123" -->

### 📚 Description

With nuxt/nuxt#28392 it is now possible to key
the context to the correct nuxt instance.

Breaking change since we need the newest nuxt version for this to work.

<!-- Describe your changes in detail -->
<!-- Why is this change required? What problem does it solve? -->

packages/storybook-addon/package.json

@@ -61,14 +61,14 @@
     "release": "pnpm changelogen --release --push && pnpm publish"
   },
   "peerDependencies": {
-    "nuxt": "^3.12.0",
+    "nuxt": "^3.13.0",
     "vite": "^5.2.0",
     "vue": "^3.4.0"
   },
   "dependencies": {
-    "@nuxt/kit": "^3.12.2",
-    "@nuxt/schema": "^3.12.2",
-    "@nuxt/vite-builder": "^3.12.2",
+    "@nuxt/kit": "^3.13.0",
+    "@nuxt/schema": "^3.13.0",
+    "@nuxt/vite-builder": "^3.13.0",
     "@rollup/plugin-replace": "^5.0.7",
     "@storybook/builder-vite": "^8.2.9",
     "@storybook/vue3": "^8.2.9",

packages/storybook-addon/src/preview.ts

@@ -35,13 +35,9 @@ setup(async (vueApp, storyContext) => {
     throw new Error('StoryContext is not provided')
   }
 
-  // This is the `nuxtApp._name`, it's the same for all stories.
-  const appId = 'nuxt-app'
-  const globalCtx = getContext(appId)
-
-  // This is the `nuxtApp.globalName`, it's different for each story.
-  const storyNuxtAppName = `nuxt-app-${key}`
-  const storyNuxtCtx = getContext(storyNuxtAppName)
+  // Create a new nuxt app for each story
+  const storyNuxtAppId = `nuxt-app-${key}`
+  const storyNuxtCtx = getContext(storyNuxtAppId)
   if (storyNuxtCtx.tryUse()) {
     // Nothing to do, the Nuxt app is already created
     return
@@ -68,11 +64,14 @@ setup(async (vueApp, storyContext) => {
   }
 
   const nuxt = createNuxtApp({
+    id: storyNuxtAppId,
     vueApp,
-    globalName: storyNuxtAppName,
   })
 
-  globalCtx.set(nuxt, true)
+  // Provide the Nuxt app as context
+  storyNuxtCtx.set(nuxt, true)
+  // ...also for calls of useNuxtApp with the default key
+  getContext('nuxt-app').set(nuxt, true)
 
   await applyPlugins(nuxt, pluginsTyped)
   await nuxt.hooks.callHook('app:created', vueApp)