fix(web): 构建后补回 assets/.gitkeep，保证新克隆可直接 go build

web/vite.config.ts

@@ -1,17 +1,31 @@
 import { fileURLToPath, URL } from 'node:url'
-import { defineConfig } from 'vite'
+import { writeFileSync } from 'node:fs'
+import { join } from 'node:path'
+import { defineConfig, type Plugin } from 'vite'
 import vue from '@vitejs/plugin-vue'
 
 const resolve = (p: string) => fileURLToPath(new URL(p, import.meta.url))
+const outDir = resolve('../server/internal/webui/assets')
+
+// emptyOutDir 会把 .gitkeep 一起删掉，导致「新克隆的仓库没构建前端时 go:embed 匹配不到文件」。
+// 构建结束后补回来，保证任何状态下 go build 都能通过。
+function keepAssetsGitkeep(): Plugin {
+  return {
+    name: 'scoreboard:keep-assets-gitkeep',
+    closeBundle() {
+      writeFileSync(join(outDir, '.gitkeep'), '')
+    },
+  }
+}
 
 export default defineConfig({
-  plugins: [vue()],
+  plugins: [vue(), keepAssetsGitkeep()],
   resolve: {
     alias: { '@': resolve('./src') },
   },
   build: {
     // 构建产物直接输出到 Go 的 embed 目录
-    outDir: resolve('../server/internal/webui/assets'),
+    outDir,
     emptyOutDir: true,
     rollupOptions: {
       input: {