feat: 添加 Lighter 适配器及相关功能，支持 trailing stops 和新的交易逻辑

docs/lighter/poseidon_crypto-main/curve/ecgfp5/u128.go

@@ -0,0 +1,29 @@
+package ecgfp5
+
+import (
+	"math/bits"
+)
+
+type U128 struct{ Hi, Lo uint64 }
+
+func U128From64(v uint64) U128 { return U128{Lo: v} }
+
+func (u U128) Add64(n uint64) (v U128) {
+	var carry uint64
+	v.Lo, carry = bits.Add64(u.Lo, n, 0)
+	v.Hi = u.Hi + carry
+	return v
+}
+
+func (u U128) Sub64(n uint64) (v U128) {
+	var borrowed uint64
+	v.Lo, borrowed = bits.Sub64(u.Lo, n, 0)
+	v.Hi = u.Hi - borrowed
+	return v
+}
+
+func (u U128) Mul64(n uint64) (dest U128) {
+	dest.Hi, dest.Lo = bits.Mul64(u.Lo, n)
+	dest.Hi += u.Hi * n
+	return dest
+}