fix(types): add "null" to LuaPrimitive and replace return "undefined" to "void" in LuaFunction

Author: quaternion

types/lua-state-native.module.d.ts

@@ -34,8 +34,8 @@ declare module '*lua-state.node' {
     | 'utf8'
 
   export type LuaValue = LuaPrimitive | LuaTable | LuaFunction | LuaValue[]
-  export type LuaPrimitive = string | number | boolean | Date | bigint
-  export type LuaFunction = (...args: LuaValue[]) => LuaValue | undefined
+  export type LuaPrimitive = string | number | boolean | Date | bigint | null
+  export type LuaFunction = (...args: LuaValue[]) => LuaValue | void
   export type LuaTable = {
     [index: string]: LuaValue | undefined
   }