fix: copy

packages/vite-plugin-uni/src/configResolved/plugins/copy.ts

 import path from 'path'
+import slash from 'slash'
 import { Plugin } from 'vite'
 import copy from 'rollup-plugin-copy'
 import { PUBLIC_DIR } from '@dcloudio/uni-cli-shared'
@@ -12,11 +13,11 @@ export function uniCopyPlugin({
   return copy({
     targets: [
       {
-        src: path.resolve(inputDir, PUBLIC_DIR),
+        src: slash(path.resolve(inputDir, PUBLIC_DIR)),
         dest: outputDir,
       },
       {
-        src: path.resolve(inputDir, 'uni_modules/*/' + PUBLIC_DIR),
+        src: slash(path.resolve(inputDir, 'uni_modules/*/' + PUBLIC_DIR)),
         dest: outputDir,
         rename: (_name, _extension, fullPath) => {
           return path.relative(inputDir, fullPath)