Fix blank flash screen and crash when flashing module zips

FlashScreen's useTerminal was a plain getter on flashAction, which was
only set in LaunchedEffect (after first composition). Since it wasn't
a Compose State, no recomposition occurred, leaving the screen stuck on
an empty LazyColumn. The unreachable TerminalComposeView meant
onEmulatorReady was never called, hanging the coroutine and eventually
crashing the process.

Pass the action from the route key directly to FlashScreen so it can
pick the correct UI path on the very first composition.

Made-with: Cursor

app/apk/src/main/java/com/topjohnwu/magisk/ui/MainActivity.kt

@@ -183,7 +183,7 @@ class MainActivity : AppCompatActivity(), SplashScreenHost {
                                             vm.startFlashing()
                                         }
                                     }
-                                    FlashScreen(vm, onBack = { navigator.pop() })
+                                    FlashScreen(vm, action = key.action, onBack = { navigator.pop() })
                                 }
                                 entry<Route.SuperuserDetail> { key ->
                                     val vm: SuperuserViewModel = androidx.lifecycle.viewmodel.compose.viewModel(

app/apk/src/main/java/com/topjohnwu/magisk/ui/flash/FlashScreen.kt

@@ -19,6 +19,7 @@ import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import com.topjohnwu.magisk.R
+import com.topjohnwu.magisk.core.Const
 import com.topjohnwu.magisk.ui.terminal.TerminalComposeView
 import top.yukonga.miuix.kmp.basic.Icon
 import top.yukonga.miuix.kmp.basic.IconButton
@@ -32,10 +33,11 @@ import top.yukonga.miuix.kmp.theme.MiuixTheme
 import com.topjohnwu.magisk.core.R as CoreR
 
 @Composable
-fun FlashScreen(viewModel: FlashViewModel, onBack: () -> Unit) {
+fun FlashScreen(viewModel: FlashViewModel, action: String, onBack: () -> Unit) {
     val flashState by viewModel.flashState.collectAsState()
     val showReboot by viewModel.showReboot.collectAsState()
     val finished = flashState != FlashViewModel.State.FLASHING
+    val useTerminal = action == Const.Value.FLASH_ZIP
 
     val statusText = when (flashState) {
         FlashViewModel.State.FLASHING -> stringResource(CoreR.string.flashing)
@@ -91,7 +93,7 @@ fun FlashScreen(viewModel: FlashViewModel, onBack: () -> Unit) {
         },
         popupHost = { }
     ) { padding ->
-        if (viewModel.useTerminal) {
+        if (useTerminal) {
             val session by viewModel.termSession.collectAsState()
             TerminalComposeView(
                 session = session,

app/apk/src/main/java/com/topjohnwu/magisk/ui/flash/FlashViewModel.kt

@@ -58,8 +58,6 @@ class FlashViewModel : BaseViewModel() {
     private val emulatorReady = CompletableDeferred<Unit>()
     val sessionCallback = TerminalSessionCallback()
 
-    val useTerminal get() = flashAction == Const.Value.FLASH_ZIP
-
     fun setTerminalView(view: TerminalView) {
         sessionCallback.terminalView = view
     }