feat(flutter): 增加 debug 服务地址编辑器

lib/core/config/app_config.dart

@@ -80,7 +80,12 @@ class AppConfig {
     Future<bool> Function(String baseUrl)? probe,
     String? fallbackBaseUrl,
   }) async {
-    for (final candidate in _probeCandidates) {
+    final candidates = <String>[
+      if (_runtimeBaseUrl.isNotEmpty) _runtimeBaseUrl,
+      for (final candidate in _probeCandidates)
+        if (candidate != _runtimeBaseUrl) candidate,
+    ];
+    for (final candidate in candidates) {
       final result = probe == null
           ? await _probeBaseUrl(candidate)
           : await _runInjectedProbe(candidate, probe);

lib/core/config/server_endpoint.dart

@@ -69,6 +69,7 @@ abstract final class ServerEndpoint {
         preferenceKey,
         normalized,
       );
+      AppConfig.applyRuntimeBaseUrl(normalized);
       return true;
     } catch (_) {
       return false;