fix: 支持明文网络请求，增强安装脚本自动卸载冲突签名，优化设置页AI配置响应

kouyu_english/lib/features/progress/progress_pages.dart

@@ -288,7 +288,7 @@ class _SettingsPageState extends State<SettingsPage> {
           style: TextStyle(fontSize: 12, color: AppColors.muted),
         ),
         DropdownButtonFormField<AiProviderType>(
-          initialValue: widget.state.aiProvider,
+          value: widget.state.aiProvider,
           decoration: const InputDecoration(
             labelText: '服务类型',
             border: OutlineInputBorder(),
@@ -313,15 +313,17 @@ class _SettingsPageState extends State<SettingsPage> {
           ],
           onChanged: (value) {
             if (value == null) return;
-            widget.state.setAiProvider(value);
-            if (value == AiProviderType.gemini &&
-                endpoint.text.trim().isEmpty) {
-              endpoint.text =
-                  'https://generativelanguage.googleapis.com/v1beta';
-              model.text = model.text.trim().isEmpty
-                  ? 'gemini-2.5-flash'
-                  : model.text;
-            }
+            setState(() {
+              widget.state.setAiProvider(value);
+              if (value == AiProviderType.gemini &&
+                  endpoint.text.trim().isEmpty) {
+                endpoint.text =
+                    'https://generativelanguage.googleapis.com/v1beta';
+                model.text = model.text.trim().isEmpty
+                    ? 'gemini-2.5-flash'
+                    : model.text;
+              }
+            });
           },
         ),
         TextField(