feat: 添加 LP 流动性池功能

新增功能:
- 添加 LPPanel 组件，支持流动性池操作
- 添加流动性 (addLiquidity): 存入 YT 代币或 WUSD 获得 ytLP
- 移除流动性 (removeLiquidity): 销毁 ytLP 获取代币
- 代币互换 (swapYT): 在池内交换 YT 代币

合约集成:
- YTRewardRouter: 0x51eEF57eC57c867AC23945f0ce21aA5A9a2C246c
- YTLPToken: 0x1b96F219E8aeE557DD8bD905a6c72cc64eA5BD7B
- YTPoolManager: 0x14246886a1E1202cb6b5a2db793eF3359d536302
- YTVault: 0x19982e5145ca5401A1084c0BF916c0E0bB343Af9
- USDY: 0x631Bd6834C50f6d2B07035c9253b4a19132E888c

UI功能:
- 显示池子 AUM、ytLP 价格、总供应量
- 显示用户 ytLP 余额和冷却时间
- Tab 切换: 添加流动性/移除流动性/代币互换
- 代币授权检查和一键授权
- 滑点容忍度设置
- 中英文翻译支持

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/i18n/locales/en.json

@@ -18,7 +18,8 @@
   "nav": {
     "wusd": "WUSD",
     "vaultTrading": "Vault Trading",
-    "factory": "Factory"
+    "factory": "Factory",
+    "lpPool": "LP Pool"
   },
   "header": {
     "title": "YT Asset Test"
@@ -147,5 +148,36 @@
     "updatePriceNotOwnerDesc": "Non-owner calls updateVaultPrices",
     "setManagerNotOwner": "Set Manager (Not Owner)",
     "setManagerNotOwnerDesc": "Non-owner calls setVaultManager"
+  },
+  "lp": {
+    "title": "YT Liquidity Pool",
+    "rewardRouter": "Reward Router Contract",
+    "ytLPToken": "ytLP Token",
+    "poolAUM": "Pool AUM",
+    "ytLPPrice": "ytLP Price",
+    "totalSupply": "Total Supply",
+    "yourBalance": "Your Balance",
+    "cooldownRemaining": "Cooldown Remaining",
+    "noCooldown": "No cooldown",
+    "addLiquidity": "Add Liquidity",
+    "addLiquidityDesc": "Deposit YT tokens or WUSD to receive ytLP tokens",
+    "removeLiquidity": "Remove Liquidity",
+    "removeLiquidityDesc": "Burn ytLP to get tokens back",
+    "swapTokens": "Swap Tokens",
+    "swapDesc": "Swap between YT tokens and WUSD in the pool",
+    "selectToken": "Select Token",
+    "amount": "Amount",
+    "slippage": "Slippage Tolerance",
+    "approveToken": "Approve Token",
+    "approveYtLP": "Approve ytLP",
+    "outputToken": "Output Token",
+    "ytLPAmount": "ytLP Amount",
+    "max": "Max",
+    "fromToken": "From Token",
+    "toToken": "To Token",
+    "swap": "Swap",
+    "cooldownNotPassed": "Cooldown not passed, please try later",
+    "insufficientOutput": "Insufficient output amount",
+    "cooldownWarning": "Cooldown remaining {{time}}, cannot remove liquidity yet"
   }
 }