@overload does not cooperate with @alias

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?

Annotations, Diagnostics/Syntax Checking

Expected Behaviour

When I define an @alias, an @overload command should be able to use it.

Actual Behaviour

I receive the error:

`fun` expected. Lua Syntax Check.(luadoc-miss-fun-after-overload)

Reproduction steps

---@alias what fun():"ok"

---@class huh
---@overload what
local huh = {}

从 @alias 和 @overload 的 Lua 文档注解处理开始，使用 issue 中的复现作为第一个运行的用例。跟踪 @overload 产生诊断 luadoc-miss-fun-after-overload 的原因。完成的标准是：基于 alias 的 overload 在没有该诊断的情况下被接受，同时现有的 overload 语法仍然有效。