feat(module): add support for vue using unplugin (#2416)

Co-authored-by: Benjamin Canac <canacb1@gmail.com>

src/plugins/app-config.ts

@@ -0,0 +1,25 @@
+import type { UnpluginOptions } from 'unplugin'
+
+import type { NuxtUIOptions } from '../unplugin'
+
+/**
+ * This plugin injects Nuxt UI configuration into the runtime build so Nuxt UI components can
+ * access it.
+ */
+export default function AppConfigPlugin(options: NuxtUIOptions & { theme: NonNullable<NuxtUIOptions['theme']> }, appConfig: Record<string, any>) {
+  return {
+    name: 'nuxt:ui:app-config',
+    enforce: 'pre',
+    resolveId(id) {
+      if (id === '#build/app.config') {
+        return 'virtual:nuxt-ui-app-config'
+      }
+    },
+    loadInclude: id => id === 'virtual:nuxt-ui-app-config',
+    load() {
+      return `
+          export default ${JSON.stringify(appConfig!)}
+        `
+    }
+  } satisfies UnpluginOptions
+}