build: do not emit .mjs in runtime directory (#2514)

build.config.ts

@@ -1,11 +1,18 @@
 import { defineBuildConfig } from 'unbuild'
 
 export default defineBuildConfig({
-  entries: [
-    {
-      input: 'src/runtime/',
-      outDir: 'dist/runtime',
-      ext: 'js'
+  externals: [
+    '#build/types/layouts'
+  ],
+  hooks: {
+    'build:prepare' (ctx) {
+      ctx.options.entries = ctx.options.entries?.filter(entry => !entry.input?.includes('src/runtime'))
+      ctx.options.entries.push({
+        builder: 'mkdist',
+        input: 'src/runtime/',
+        outDir: 'dist/runtime',
+        ext: 'js'
+      })
     }
-  ]
+  }
 })

package.json

@@ -120,10 +120,5 @@
     "hooks": {
       "after:bump": "npx changelogen@latest --no-commit --no-tag --output --r $(node -p \"require('./package.json').version\")"
     }
-  },
-  "build": {
-    "externals": [
-      "#build/types/layouts"
-    ]
   }
 }