fix(h5-shop): harden iOS WeChat scan after login with hard nav and recover UI

Root cause is JSSDK entry-URL mismatch after SPA post-OAuth, not camera permission. Hard-navigate on iOS, keep OAuth query in sign URL, skip redundant bind OAuth, and prompt refresh/re-auth on failure.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/h5-shop/src/lib/wechat-auth.ts

@@ -169,11 +169,12 @@ export async function loginShopWithWechat(): Promise<ShopSessionPayload | null |
 }
 
 /** 短信登录成功后于微信内自动发起 OAuth，绑定 openId 便于后续免登 */
-export async function bindShopWechatAfterSmsLogin(): Promise<void> {
+export async function bindShopWechatAfterSmsLogin(session?: ShopSessionPayload): Promise<'skipped' | void> {
   const config = await fetchClientConfig();
-  if (!isWxAuthorizeEnabled(config)) return;
-  if (!isWechatEnv()) return;
-  // OAuth 整页回跳后 iOS 需用入场 URL 重配 JSSDK；标记下次扫码加长预热
+  if (!isWxAuthorizeEnabled(config)) return 'skipped';
+  if (!isWechatEnv()) return 'skipped';
+  // 已绑定则勿再 OAuth：每次 OAuth 回跳都会重置 iOS JSSDK 入场 URL，易导致扫码失败
+  if (session?.account?.hasWechat) return 'skipped';
   markScanWarmupAfterAuth();
   await weixinSdk.login();
 }