The type of keys used to index [] tables is not checked

还没有人认领这个 Issue。

### 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

Some warning should be raised if you use [5] on a table, for example.

### Actual Behaviour

In the expression `tbl[x]`, the type of x is not checked at all

### Reproduction steps

```lua
---@type table -- or string[]
local IntStr = {}
---@type table
local StrInt = {}
IntStr[5] = "hi" -- ok
IntStr["a"] = "b" -- "a" should produce a warning
StrInt["a"] = 5 -- ok
StrInt[5] = 6 -- 5 should produce a warning
```

### Additional Notes

Probably related to #1861

### Log File

_No response_

从 issue 中的 Lua 复现开始，检查表索引的类型检查路径。验证不匹配的键类型对于整数键表和字符串键表都会产生警告，同时匹配的赋值仍然有效。

由索引模型根据 Issue 内容生成。