fix(types): fix vitepress/theme type

close #489, close #438, close #494, close #442

package.json

@@ -11,7 +11,8 @@
     "bin",
     "dist",
     "types",
-    "client.d.ts"
+    "client.d.ts",
+    "theme.d.ts"
   ],
   "scripts": {
     "dev": "run-s dev-shared dev-start",

theme.d.ts

@@ -1,3 +1,9 @@
 // so that users can do `import DefaultTheme from 'vitepress/theme'`
-import DefaultTheme from './dist/client/theme-default/index'
-export default DefaultTheme
+import { ComponentOptions } from 'vue'
+
+declare const defaultTheme: {
+  Layout: ComponentOptions
+  NotFound: ComponentOptions
+}
+
+export default defaultTheme