Ability to use specific enum keys as params

It would be nice to be able to use specific enum keys as params. For example today if you try to do something like this:

```
---@enum TestEnum
TestEnum = {
ONE = 1,
TWO = 2,
THREE = 3,
}

---@param test TestEnum.ONE
local function test(test)
end

test(TestEnum.ONE)
test(1)
```

You will get an error:
```
Cannot assign `integer` to parameter `TestEnum.ONE`.
- `integer` cannot match `TestEnum.ONE`
- Type `integer` cannot match `TestEnum.ONE`
- Type `number` cannot match `TestEnum.ONE`
```

Interestingly lls understands that TestEnum.ONE is a real thing just not that it is equal to TestEnum.ONE or 1. For exmaple if you try this:
```
---@enum TestEnum
TestEnum = {
ONE = 1,
TWO = 2,
THREE = 3,
}

---@param test TestEnum.One
local function test(test)
end

test(TestEnum.ONE)
test(1)
```
You will get an error:
```
---@param test TestEnum.NonEnumValue
```

No file, test, or entry point is identified in the issue, so begin by locating enum type checking and parameter-assignability handling in lua-language-server. Done means TestEnum.ONE is accepted for TestEnum.ONE and its underlying value 1 is handled consistently, while invalid enum keys remain rejected.

Written by the indexing model from the issue text.