add lua engine skeleton

internal/engine/lua/pool.go

@@ -0,0 +1,35 @@
+package lua
+
+import (
+	"sync"
+
+	lua "github.com/yuin/gopher-lua"
+)
+
+type LuaPool struct {
+	pool sync.Pool
+}
+
+func NewLuaPool() *LuaPool {
+	return &LuaPool{
+		pool: sync.Pool{
+			New: func() any {
+				L := lua.NewState()
+				
+				return L
+			},
+		},
+	}
+}
+
+func (lp *LuaPool) Get() *lua.LState {
+	return lp.pool.Get().(*lua.LState)
+}
+
+func (lp *LuaPool) Put(L *lua.LState) {
+	L.Close()
+
+	newL := lua.NewState()
+	
+	lp.pool.Put(newL)
+}