BUG: 当_ENV作为多重赋值的第一个变量时, 后续变量会错误的识别成局部变量.

### How are you using the lua-language-server?

Visual Studio Code Extension (sumneko.lua)

### Which OS are you using?

Windows

### What is the issue affecting?

Type Checking

### Expected Behaviour

这是非常罕见的场景, 并且建议避免编写这种代码.

```lua
local env = _ENV
_ENV, a = {}, 1
env.print(env.a, a) -- 1 nil
```
使用parser.compile函数解析得到的state.ast.locals会多出错误的局部变量_ENV和a.
整个多重赋值语句都会识别成local变量定义, 不管是a, a.x, a[1]形式, 生成的ast.type字段都会被错误的标识成'local'.

同时也会导致[vscode插件](https://github.com/LuaLS/lua-language-server)错误提示.

### Actual Behaviour

错误的将多重赋值语句, 识别成了局部变量定义语句.

### Reproduction steps

.

### Additional Notes

_No response_

### Log File

_No response_

Start with parser.compile and inspect state.ast.locals for the supplied `_ENV, a = {}, 1` example, comparing the generated AST with the assignment targets. Done means the multiple assignment no longer creates false local variables or produces the related VS Code diagnostic, including for `a`, `a.x`, and `a[1]` targets.

Written by the indexing model from the issue text.