升级Vue3，iView替换ElementPlus

- 删除babel配置、更新依赖与入口初始化
- 全量替换UI组件、样式适配，新增迁移文档与标签/过滤器自动化替换脚本

buyer/scripts/fix-slots.js

@@ -0,0 +1,54 @@
+#!/usr/bin/env node
+const fs = require("fs");
+const path = require("path");
+
+const ROOT = path.join(__dirname, "..");
+
+function walkDir(dir, files = []) {
+  for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
+    const full = path.join(dir, entry.name);
+    if (entry.isDirectory()) walkDir(full, files);
+    else if (entry.name.endsWith(".vue")) files.push(full);
+  }
+  return files;
+}
+
+function fix(content) {
+  let c = content;
+
+  c = c.replace(
+    /<template #default="(\{[^"]+\})" #([a-zA-Z0-9_-]+)>/g,
+    '<template #$2="$1">'
+  );
+
+  c = c.replace(
+    /<div([^>]*) #footer([^>]*)>/g,
+    '<template #footer><div$1$2>'
+  );
+  c = c.replace(/<\/div>\s*(?=<\/el-dialog>)/g, "</div></template>");
+
+  c = c.replace(/<span #append>/g, "<template #append><span>");
+  c = c.replace(/<\/span><\/el-input/g, "</span></template></el-input");
+  c = c.replace(/><span #append>/g, "><template #append><span>");
+
+  c = c.replace(/<el-button #append/g, "<template #append><el-button");
+  c = c.replace(
+    /<\/el-button>(\s*<\/el-input>)/g,
+    "</el-button></template>$1"
+  );
+
+  c = c.replace(/<template #desc\b/g, "<template #default");
+
+  return c;
+}
+
+let count = 0;
+for (const file of walkDir(path.join(ROOT, "src"))) {
+  const original = fs.readFileSync(file, "utf8");
+  const fixed = fix(original);
+  if (fixed !== original) {
+    fs.writeFileSync(file, fixed);
+    count++;
+  }
+}
+console.log(`Fixed slots in ${count} files`);