build: add vue 2.x compat package

packages/vue/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "vue",
+  "version": "3.0.0-alpha.1",
+  "description": "vue",
+  "main": "index.js",
+  "module": "dist/vue.esm-bundler.js",
+  "typings": "dist/index.d.ts",
+  "unpkg": "dist/vue.global.js",
+  "buildOptions": {
+    "name": "Vue",
+    "compat": true,
+    "formats": ["esm", "cjs", "global", "esm-browser"]
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/vuejs/vue.git"
+  },
+  "keywords": [
+    "vue"
+  ],
+  "author": "Evan You",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/vuejs/vue/issues"
+  },
+  "homepage": "https://github.com/vuejs/vue/tree/dev/packages/vue#readme",
+  "dependencies": {
+    "@vue/renderer-dom": "3.0.0-alpha.1"
+  }
+}