[fix] typescript template

[neko1990]

修几个ts模板和语法的问题：

1. 由 commit 88c09b 引入两个 + 模板报错：

   
   ret 'for (let _e of ' + 'this.' + + fieldName + ') { _e?.resolve(tables); }'

|ERROR|===> "One or more errors occurred. ((44,49) : error : Unexpected value keys / Type: string. Cannot negate(-)/positive(+) a non-numeric value)" |ERROR|===> "(44,49) : error : Unexpected value keys / Type: string. Cannot negate(-)/positive(+) a non-numeric value" |ERROR|run failed!!!

2. 最初这段末尾少一个 `+` 模板报错 [commit 3d1fae](https://github.com/focus-creative-games/luban/commit/3d1faed5deb02035ce5c4d281a71b3e24f6d739f)  

ret 'foreach (var [_, _e] of ' + fieldName ') { _e?.resolve(tables); }'

|ERROR|===> "One or more errors occurred. ((46,52) : error : Invalid target function multiRows4 (string))" |ERROR|===> "(46,52) : error : Invalid target function multiRows4 (string)" |ERROR|run failed!!!

3. typescript 没有 foreach 关键字，对 map 的迭代也用 for
4. 用 let 替换 var，减小scope