init: 初始化 AssetX 项目仓库

包含 webapp（Next.js 用户端）、webapp-back（Go 后端）、
antdesign（管理后台）、landingpage（营销落地页）、
数据库 SQL 和配置文件。

webapp/hooks/useLendingWithdraw.ts

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+import { useState, useCallback, useEffect } from 'react'
+import { useAccount, useWriteContract, useWaitForTransactionReceipt } from 'wagmi'
+import { parseUnits } from 'viem'
+import { abis, getContractAddress } from '@/lib/contracts'
+import { useTokenList } from './useTokenList'
+import { handleContractCatchError, isValidAmount, parseContractError } from '@/lib/errors'
+import { WITHDRAW_GAS_LIMIT } from '@/lib/constants'
+
+type WithdrawStatus = 'idle' | 'withdrawing' | 'success' | 'error'
+
+export function useLendingWithdraw() {
+  const { address, chainId } = useAccount()
+  const { bySymbol } = useTokenList()
+  const usdcToken = bySymbol['USDC']
+  const [status, setStatus] = useState<WithdrawStatus>('idle')
+  const [error, setError] = useState<string | null>(null)
+
+  const {
+    writeContractAsync: withdrawWrite,
+    data: withdrawHash,
+    isPending: isWithdrawPending,
+    reset: resetWithdraw,
+  } = useWriteContract()
+
+  const {
+    isLoading: isWithdrawConfirming,
+    isSuccess: isWithdrawSuccess,
+    isError: isWithdrawError,
+    error: withdrawReceiptError,
+  } = useWaitForTransactionReceipt({ hash: withdrawHash })
+
+  const executeWithdraw = useCallback(async (amount: string) => {
+    if (status !== 'idle') return false
+    if (!address || !chainId || !usdcToken || !amount) {
+      setError('Missing required parameters')
+      return false
+    }
+    if (!isValidAmount(amount)) {
+      setError('Invalid amount')
+      return false
+    }
+
+    try {
+      setError(null)
+      setStatus('withdrawing')
+
+      const lendingProxyAddress = getContractAddress('lendingProxy', chainId)
+      if (!lendingProxyAddress) {
+        throw new Error('Contract not deployed on this chain')
+      }
+
+      const usdcDecimals = usdcToken.onChainDecimals ?? usdcToken.decimals
+      const amountInWei = parseUnits(amount, usdcDecimals)
+
+      await withdrawWrite({
+        address: lendingProxyAddress,
+        abi: abis.lendingProxy,
+        functionName: 'withdraw',
+        args: [amountInWei],
+        gas: WITHDRAW_GAS_LIMIT,
+      })
+
+      return true
+    } catch (err: unknown) {
+      handleContractCatchError(err, 'Withdraw failed', setError, setStatus as (s: string) => void)
+      return false
+    }
+  }, [address, chainId, withdrawWrite, usdcToken, status])
+
+  useEffect(() => {
+    if (isWithdrawSuccess && status === 'withdrawing') {
+      setStatus('success')
+    }
+  }, [isWithdrawSuccess, status])
+
+  useEffect(() => {
+    if (isWithdrawError && status === 'withdrawing') {
+      setError(parseContractError(withdrawReceiptError))
+      setStatus('error')
+    }
+  }, [isWithdrawError, status, withdrawReceiptError])
+
+  const reset = useCallback(() => {
+    setStatus('idle')
+    setError(null)
+    resetWithdraw()
+  }, [resetWithdraw])
+
+  return {
+    status,
+    error,
+    isLoading: isWithdrawPending || isWithdrawConfirming,
+    withdrawHash,
+    executeWithdraw,
+    reset,
+  }
+}