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/lib/errors.ts

@@ -0,0 +1,77 @@
+/**
+ * 合约错误处理工具
+ */
+
+const USER_REJECTION_PATTERNS = [
+  'User rejected',
+  'User denied',
+  'user rejected',
+  'rejected the request',
+]
+
+/** 判断是否为用户拒绝交易 */
+export function isUserRejection(err: unknown): boolean {
+  const msg = getErrorMessage(err)
+  return USER_REJECTION_PATTERNS.some(pattern => msg.includes(pattern))
+}
+
+/** 解析合约 revert 原因 */
+export function parseContractError(err: unknown, fallback = 'Transaction failed'): string {
+  if (!err) return fallback
+  const msg = getErrorMessage(err)
+  const match =
+    msg.match(/reverted with reason string '(.+?)'/) ||
+    msg.match(/execution reverted: (.+?)(?:\n|$)/) ||
+    msg.match(/reverted: (.+?)(?:\n|$)/)
+  if (match) return match[1]
+  const short = getShortMessage(err)
+  if (short) return short
+  return fallback
+}
+
+/** 统一 catch 块处理 */
+export function handleContractCatchError(
+  err: unknown,
+  fallback: string,
+  setError: (msg: string) => void,
+  setStatus: (status: string) => void,
+): void {
+  if (isUserRejection(err)) {
+    setError('Transaction cancelled')
+    setStatus('idle')
+  } else {
+    setError(parseContractError(err, fallback))
+    setStatus('error')
+  }
+}
+
+/** 校验金额是否为合法正数 */
+export function isValidAmount(amount: string): boolean {
+  const n = Number(amount)
+  return !isNaN(n) && isFinite(n) && n > 0
+}
+
+/** 安全解析浮点数，NaN/Infinity → 0 */
+export function safeParseFloat(value: string | number): number {
+  const n = typeof value === 'string' ? parseFloat(value) : value
+  if (isNaN(n) || !isFinite(n)) return 0
+  return n
+}
+
+function getErrorMessage(err: unknown): string {
+  if (err instanceof Error) return err.message
+  if (typeof err === 'object' && err !== null) {
+    const e = err as Record<string, unknown>
+    if (typeof e.message === 'string') return e.message
+    if (typeof e.shortMessage === 'string') return e.shortMessage
+  }
+  return String(err)
+}
+
+function getShortMessage(err: unknown): string | undefined {
+  if (typeof err === 'object' && err !== null) {
+    const e = err as Record<string, unknown>
+    if (typeof e.shortMessage === 'string') return e.shortMessage
+  }
+  return undefined
+}