add lua sample and definition file in lua

meta/uname.lua

@@ -0,0 +1,25 @@
+---@meta uname
+
+---@class unamelib
+local uname = {}
+
+---@param x integer
+---@return integer
+---@nodiscard
+function uname.numid(x) end
+
+---@param x integer
+---@return integer
+---@nodiscard
+function uname.plusone(x) end
+
+---@class uname
+---@field sysname string
+---@field machine string
+---@field release string
+---@field version string
+
+---@return uname
+function uname.uname() end
+
+return uname