fix(client): 联系/购买渠道卡点击外部打开(修空 onTap)+ 桌面账户子导航复现测试

- channel_launch: @→t.me / 邮箱→mailto / 域名→https,外部打开
- 联系页(桌面)/联系&兑换子页(移动)渠道卡接上 onTap
- account_desktop_nav_test: 证明桌面设置/兑换/联系/订单导航正常(231 全绿)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013nMthbVEmQquxBRKb9Fj8u

client/ios/Podfile.lock

@@ -2,20 +2,26 @@ PODS:
   - Flutter (1.0.0)
   - flutter_secure_storage (6.0.0):
     - Flutter
+  - open_filex (0.0.2):
+    - Flutter
 
 DEPENDENCIES:
   - Flutter (from `Flutter`)
   - flutter_secure_storage (from `.symlinks/plugins/flutter_secure_storage/ios`)
+  - open_filex (from `.symlinks/plugins/open_filex/ios`)
 
 EXTERNAL SOURCES:
   Flutter:
     :path: Flutter
   flutter_secure_storage:
     :path: ".symlinks/plugins/flutter_secure_storage/ios"
+  open_filex:
+    :path: ".symlinks/plugins/open_filex/ios"
 
 SPEC CHECKSUMS:
   Flutter: cabc95a1d2626b1b06e7179b784ebcf0c0cde467
   flutter_secure_storage: 1ed9476fba7e7a782b22888f956cce43e2c62f13
+  open_filex: 432f3cd11432da3e39f47fcc0df2b1603854eff1
 
 PODFILE CHECKSUM: 953f21eefd3c2835779b3cd836901e88e3270439