Fix root detection for KernelSU

Use libsu's Shell API instead of Runtime.exec("su -c ...") for root
detection. The previous approach assumed su is in PATH, which works
for Magisk but not for KernelSU where su has a different path.

app/src/github/java/io/nekohasekai/sfa/vendor/RootInstaller.kt

@@ -18,16 +18,6 @@ import kotlin.coroutines.resumeWithException
 
 object RootInstaller {
 
-    suspend fun checkAccess(): Boolean = withContext(Dispatchers.IO) {
-        try {
-            val process = Runtime.getRuntime().exec("su -c echo test")
-            val exitCode = process.waitFor()
-            exitCode == 0
-        } catch (e: Exception) {
-            false
-        }
-    }
-
     suspend fun install(apkFile: File) {
         withContext(Dispatchers.IO) {
             bindRootService().use { handle ->

app/src/main/java/io/nekohasekai/sfa/compose/screen/settings/ProfileOverrideScreen.kt

@@ -58,6 +58,7 @@ import androidx.navigation.NavController
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.LifecycleEventObserver
 import io.nekohasekai.sfa.R
+import io.nekohasekai.sfa.bg.RootClient
 import io.nekohasekai.sfa.compose.topbar.OverrideTopBar
 import io.nekohasekai.sfa.database.Settings
 import io.nekohasekai.sfa.compose.screen.profileoverride.PerAppProxyScanner
@@ -206,18 +207,7 @@ fun ProfileOverrideScreen(navController: NavController) {
                         onCheckedChange = { checked ->
                             if (checked && !autoRedirect) {
                                 scope.launch {
-                                    val hasRoot =
+                                    val hasRoot = RootClient.checkRootAvailable()
-                                        withContext(Dispatchers.IO) {
-                                            try {
-                                                val process = Runtime.getRuntime().exec("su -c id")
-                                                process.inputStream.close()
-                                                process.outputStream.close()
-                                                process.errorStream.close()
-                                                process.waitFor() == 0
-                                            } catch (e: Exception) {
-                                                false
-                                            }
-                                        }
                                     if (hasRoot) {
                                         autoRedirect = true
                                         withContext(Dispatchers.IO) {

app/src/other/java/io/nekohasekai/sfa/vendor/ApkInstaller.kt

@@ -3,6 +3,7 @@ package io.nekohasekai.sfa.vendor
 import android.content.Context
 import io.nekohasekai.sfa.Application
 import io.nekohasekai.sfa.bg.BoxService
+import io.nekohasekai.sfa.bg.RootClient
 import io.nekohasekai.sfa.database.Settings
 import io.nekohasekai.sfa.utils.HookStatusClient
 import io.nekohasekai.sfa.xposed.XposedActivation
@@ -62,7 +63,7 @@ object ApkInstaller {
         return when (method) {
             InstallMethod.PACKAGE_INSTALLER -> canSystemSilentInstall()
             InstallMethod.SHIZUKU -> ShizukuInstaller.isAvailable() && ShizukuInstaller.checkPermission()
-            InstallMethod.ROOT -> RootInstaller.checkAccess()
+            InstallMethod.ROOT -> RootClient.checkRootAvailable()
         }
     }
 }

app/src/other/java/io/nekohasekai/sfa/vendor/Vendor.kt

@@ -8,6 +8,7 @@ import androidx.camera.core.ImageAnalysis
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import io.nekohasekai.sfa.Application
 import io.nekohasekai.sfa.R
+import io.nekohasekai.sfa.bg.RootClient
 import io.nekohasekai.sfa.database.Settings
 import io.nekohasekai.sfa.compose.screen.qrscan.QRCodeCropArea
 import io.nekohasekai.sfa.update.UpdateCheckException
@@ -135,7 +136,7 @@ object Vendor : VendorInterface {
                 }
                 true
             }
-            "ROOT" -> RootInstaller.checkAccess()
+            "ROOT" -> RootClient.checkRootAvailable()
             else -> false
         }
     }

app/src/otherLegacy/java/io/nekohasekai/sfa/vendor/ApkInstaller.kt

@@ -2,6 +2,7 @@ package io.nekohasekai.sfa.vendor
 
 import android.content.Context
 import io.nekohasekai.sfa.Application
+import io.nekohasekai.sfa.bg.RootClient
 import io.nekohasekai.sfa.database.Settings
 import io.nekohasekai.sfa.utils.HookStatusClient
 import io.nekohasekai.sfa.xposed.XposedActivation
@@ -43,7 +44,7 @@ object ApkInstaller {
         val method = getConfiguredMethod()
         return when (method) {
             InstallMethod.PACKAGE_INSTALLER -> canSystemSilentInstall()
-            InstallMethod.ROOT -> RootInstaller.checkAccess()
+            InstallMethod.ROOT -> RootClient.checkRootAvailable()
         }
     }
 }

app/src/otherLegacy/java/io/nekohasekai/sfa/vendor/Vendor.kt

@@ -8,6 +8,7 @@ import androidx.camera.core.ImageAnalysis
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import io.nekohasekai.sfa.Application
 import io.nekohasekai.sfa.R
+import io.nekohasekai.sfa.bg.RootClient
 import io.nekohasekai.sfa.database.Settings
 import io.nekohasekai.sfa.compose.screen.qrscan.QRCodeCropArea
 import io.nekohasekai.sfa.update.UpdateCheckException
@@ -125,7 +126,7 @@ object Vendor : VendorInterface {
             "PACKAGE_INSTALLER" -> {
                 ApkInstaller.canSystemSilentInstall()
             }
-            "ROOT" -> RootInstaller.checkAccess()
+            "ROOT" -> RootClient.checkRootAvailable()
             else -> false
         }
     }