Extending alias functionality [Suggestion]

Good day, my suggestion is quite unusual - I'm requesting an additional functionality for aliases, basically adding ability to define regexp for string-based aliases. For example I have something like this:

---@alias Identifier string

That makes type check that Identifier is a string, but don't check if identifier need a custom structure, for example if correct structure is something like namespace:path it can't be validated with LLS.

If on another hand I can able to add a regexp to it:

---@alias Identifier string("^[^:]*:[^:]*$")

Then it will automatically check if identifier is valid

首先检查现有的别名类型检查行为，以及 LuaLS 如何表示基于字符串的类型。需要在实现之前定义所需的语法和正则表达式语义。完成内容应包括根据指定模式验证受正则表达式约束的别名，例如 Identifier。