Diagnostics for class array

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### 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

When a class is matched with its array it should produce a diagnostic error.

### Actual Behaviour

No diagnostic error is produced when a class array is matched with a class.

### Reproduction steps

1. Paste the following code:
```lua
---@class classA
local a

---@type classA[]
local b

---@param param1 classA[]
---@return classA
local function testFunc(param1)
param1 = a
return b
end

local result = testFunc(a)
```
2. Assigning `param1`, returning `b` and calling `testFunc` with `a` should all produce diagnostic errors, but no diagnostic error is produced.

### Additional Notes

Another class, such as `classB` can be matched with `classA[]` without error.

### Log File

_No response_

Run the Lua reproduction in the Visual Studio Code extension and inspect the type-checking diagnostic entry point for class-versus-array compatibility. Verify that assigning param1, returning b, and calling testFunc(a) each produce diagnostics, while the classB comparison remains covered by the existing behavior.

Written by the indexing model from the issue text.