stub `prototype` and `optionMergeStrategies` for vue3 compat

Environment

• Operating System: Linux
• Node Version: v14.18.1
• Nuxt Version: 2.16.0-27285136.ab1c6cb4
• Package Manager: yarn@1.22.17
• Bundler: Webpack
• User Config: plugins, bridge, target, ssr, buildModules
• Runtime Modules: -
• Build Modules: @nuxt/bridge@3.0.0-27286006.a08b435

Reproduction

https://codesandbox.io/s/gracious-wildflower-g27zf

Describe the bug

The vueApp provided by nuxtApp in a plugin doesn't mock all vue properties, which make some libraries fail. I encountered so far prototype (with VueTailwind, as in the reproduction above) and config.optionMergeStrategies (with VueApollo).

Additional context

--- a/node_modules/@nuxt/bridge/dist/runtime/app.plugin.mjs
+++ b/node_modules/@nuxt/bridge/dist/runtime/app.plugin.mjs
@@ -23,7 +23,8 @@ export default (ctx, inject) => {
     vueApp: {
       component: Vue.component.bind(Vue),
       config: {
-        globalProperties: {}
+        globalProperties: {},
+        optionMergeStrategies: Vue.config.optionMergeStrategies
       },
       directive: Vue.directive.bind(Vue),
       mixin: Vue.mixin.bind(Vue),
@@ -33,7 +34,8 @@ export default (ctx, inject) => {
       use (vuePlugin) {
         vuePlugin.install(this)
       },
-      version: Vue.version
+      version: Vue.version,
+      prototype: {}
     },
     provide: inject,
     globalName: 'nuxt',

fixed it for me.

Logs

No response

Start with the generated runtime file node_modules/@nuxt/bridge/dist/runtime/app.plugin.mjs and trace it back to the corresponding source in the bridge repository. Run the linked CodeSandbox reproduction to confirm the missing vueApp properties and verify that VueTailwind and VueApollo no longer fail when both properties are exposed.