fix(android): keep VPN running when pressing back (#2546)

easytier-gui/src-tauri/gen/android/app/src/main/java/com/kkrainbow/easytier/MainActivity.kt

@@ -3,9 +3,16 @@ package com.kkrainbow.easytier
 import android.content.Intent
 import android.os.Build
 import android.os.Bundle
+import androidx.activity.OnBackPressedCallback
+
 class MainActivity : TauriActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
+        onBackPressedDispatcher.addCallback(this, object : OnBackPressedCallback(true) {
+            override fun handleOnBackPressed() {
+                moveTaskToBack(true)
+            }
+        })
         initService()
     }
 
@@ -17,4 +24,4 @@ class MainActivity : TauriActivity() {
             startService(serviceIntent)
         }
     }
-}
+}