vararg overload issue

If you have a function which takes in only a vararg and you only overload it, the input type is as expected just each of the overloads:

---@overload fun(param1: "test", param2: string)
---@overload fun(param1: "test2", param2: number)
---@overload fun(param1: "test3", param2: boolean, param3: number)
local function test(...)
end

test()

However, if you have a param before the vararg, the input type always becomes param, ...any:

---@overload fun(param1: "test", param2: string)
---@overload fun(param1: "test2", param2: number)
---@overload fun(param1: "test3", param2: boolean, param3: number)
local function test(param1, ...)
end

test()

首先重现 issue 中带注释的两个 Lua 示例，并比较两种 vararg 形式推断出的签名。跟踪 overload 和 vararg 类型处理的入口点，然后验证参数位于 vararg 之前的情况会保留 overload 特定的参数类型，而不是将其合并为 ...any。