fix: 修复 Flutter Web 生产环境 API 地址未生效的问题

- NetworkConfig.baseUrl 改为使用 ApiEndpoints.baseUrl
- 确保构建时 --dart-define=ENV=prod 能正确切换环境

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

flutter_monisuo/build/web/flutter_bootstrap.js

@@ -37,6 +37,6 @@ _flutter.buildConfig = {"engineRevision":"e4b8dca3f1b4ede4c30371002441c88c12187e
 
 _flutter.loader.load({
   serviceWorkerSettings: {
-    serviceWorkerVersion: "3100103420" /* Flutter's service worker is deprecated and will be removed in a future Flutter release. */
+    serviceWorkerVersion: "2084931057" /* Flutter's service worker is deprecated and will be removed in a future Flutter release. */
   }
 });

flutter_monisuo/build/web/main.dart.js

@@ -93222,7 +93222,7 @@ return A.J($async$nV,r)}}
 A.CF.prototype={
 J(a){var s=null,r=this.a8B()
 return A.b7l(new A.zA(new A.Et(A.atZ(s,s,s,s,s,B.ap,s,s,s,s,B.a7v,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s,s),B.Jn,this.ga8q(),s),s),r)},
-a8B(){var s,r=null,q=new A.AI(),p=A.b3D("http://localhost:5010",B.qF,A.aD(["Content-Type","application/json"],t.N,t.z),B.qF),o=new A.QF(A.c([B.Ll],t.i6))
+a8B(){var s,r=null,q=new A.AI(),p=A.b3D("http://8.155.172.147:5010",B.qF,A.aD(["Content-Type","application/json"],t.N,t.z),B.qF),o=new A.QF(A.c([B.Ll],t.i6))
 o.a2(o,B.WA)
 s=new A.aer($,o,$,new A.ahG(51200),!1)
 s.Ya$=p