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

im/scripts/fix-deep.js

@@ -0,0 +1,21 @@
+const fs = require("fs");
+const path = require("path");
+
+function walk(dir, files = []) {
+  for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
+    const full = path.join(dir, entry.name);
+    if (entry.isDirectory()) walk(full, files);
+    else if (/\.(vue|less)$/.test(entry.name)) files.push(full);
+  }
+  return files;
+}
+
+const root = path.join(__dirname, "../src");
+for (const file of walk(root)) {
+  let content = fs.readFileSync(file, "utf8");
+  const next = content.replace(/\/deep\/\s*([^\{]+)\{/g, ":deep($1) {");
+  if (next !== content) {
+    fs.writeFileSync(file, next);
+    console.log("fixed:", file);
+  }
+}