feat: add configurable main page back behavior (#870)

* feat: add configurable main page back behavior

Add setting to control whether back button exits directly or returns to first tab

* update

---------

Co-authored-by: bggRGjQaUbCoE <githubaccount56556@proton.me>

lib/pages/setting/models/style_settings.dart

@@ -623,6 +623,17 @@ List<SettingsModel> get styleSettings => [
         subtitle: '删除或调换Navbar',
         leading: const Icon(Icons.toc_outlined),
       ),
+      SettingsModel(
+        settingsType: SettingsType.sw1tch,
+        title: '返回时直接退出',
+        subtitle: '开启后在主页任意tab按返回键都直接退出，关闭则先回到Navbar的第一个tab',
+        leading: const Icon(Icons.exit_to_app_outlined),
+        setKey: SettingBoxKey.directExitOnBack,
+        defaultVal: false,
+        onChanged: (value) {
+          Get.find<MainController>().directExitOnBack = value;
+        },
+      ),
       if (Platform.isAndroid)
         SettingsModel(
           settingsType: SettingsType.normal,