types(Poppperjs): export types (#8165)

packages/vant-popperjs/rollup.config.js

@@ -14,5 +14,8 @@ export default {
       format: 'esm',
     },
   ],
-  plugins: [nodeResolve(), babel({ babelHelpers: 'runtime' })],
+  plugins: [
+    babel({ babelHelpers: 'runtime', extensions: ['.js', '.ts'] }),
+    nodeResolve(),
+  ],
 };

packages/vant-popperjs/src/index.ts

@@ -1,4 +1,6 @@
 import { createPopper } from '@popperjs/core/lib/popper-lite';
 import offsetModifier from '@popperjs/core/lib/modifiers/offset';
+import type { Instance, Placement } from '@popperjs/core';
 
 export { createPopper, offsetModifier };
+export type { Instance, Placement };