Add showImmersiveStopButton setting and top-right X button overlay

app/src/main/java/com/mindmachine/mvp/MainActivity.kt

@@ -48,6 +48,7 @@ import androidx.compose.foundation.Image
 import androidx.compose.foundation.Image
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Add
+import androidx.compose.material.icons.filled.Close
 import androidx.compose.material.icons.filled.Delete
 import androidx.compose.material.icons.filled.PlayArrow
 import androidx.compose.material.icons.filled.Settings
@@ -597,6 +598,8 @@ fun ActiveSessionScreen(vm: MainViewModel, onFinish: () -> Unit, onBackToEntry:
     }
     var brightnessOverlayVisible by remember { mutableStateOf(false) }
     var brightnessOverlayToken by remember { mutableIntStateOf(0) }
+    var stopButtonVisible by remember { mutableStateOf(false) }
+    var stopButtonToken by remember { mutableIntStateOf(0) }
     val timingLogTag = "MindMachineTiming"
 
     LaunchedEffect(brightnessOverlayToken) {
@@ -642,12 +645,24 @@ fun ActiveSessionScreen(vm: MainViewModel, onFinish: () -> Unit, onBackToEntry:
                 detectTapGestures {
                     brightnessOverlayVisible = true
                     brightnessOverlayToken++
+                    if (ui.settings.showImmersiveStopButton && immersiveFullscreen) {
+                        stopButtonVisible = true
+                        stopButtonToken++
+                    }
                     if (!immersiveFullscreen) {
                         showOverlay = !showOverlay
                     }
                 }
             }
     ) {
+        // Auto-hide stop button after 3 seconds of visibility
+        LaunchedEffect(stopButtonToken) {
+            if (stopButtonVisible) {
+                delay(3000)
+                stopButtonVisible = false
+            }
+        }
+
         if (isVisualMode) {
             AndroidView(
                 modifier = Modifier.fillMaxSize(),
@@ -715,6 +730,26 @@ fun ActiveSessionScreen(vm: MainViewModel, onFinish: () -> Unit, onBackToEntry:
             }
         }
 
+        // Stop button in immersive mode (top-right)
+        if (stopButtonVisible && ui.settings.showImmersiveStopButton) {
+            IconButton(
+                onClick = {
+                    vm.stop()
+                    onFinish()
+                },
+                modifier = Modifier
+                    .align(Alignment.TopEnd)
+                    .padding(top = 16.dp, end = 16.dp)
+            ) {
+                Icon(
+                    imageVector = Icons.Filled.Close,
+                    contentDescription = "Stop",
+                    tint = Color.White,
+                    modifier = Modifier.size(28.dp)
+                )
+            }
+        }
+
         if (showOverlay) {
             Column(
                 Modifier
@@ -1233,6 +1268,18 @@ fun SettingsScreen(vm: MainViewModel, onRemoveAds: () -> Unit) {
             Text("Show immersive bottom progress bar", color = MaterialTheme.colorScheme.onBackground)
         }
 
+        Row(verticalAlignment = Alignment.CenterVertically) {
+            Checkbox(checked = ui.settings.showImmersiveStopButton, onCheckedChange = vm::updateShowImmersiveStopButton)
+            Column {
+                Text("Show stop button in immersive mode", color = MaterialTheme.colorScheme.onBackground)
+                Text(
+                    "If off, swipe from edge to display back button",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onBackground.copy(alpha = 0.7f)
+                )
+            }
+        }
+
         Row(verticalAlignment = Alignment.CenterVertically) {
             Checkbox(checked = ui.settings.preferLowestRefreshRate, onCheckedChange = vm::updatePreferLowestRefreshRate)
             Text("Prefer lowest display refresh rate during sessions", color = MaterialTheme.colorScheme.onBackground)

app/src/main/java/com/mindmachine/mvp/data/SettingsRepository.kt

@@ -20,6 +20,7 @@ class SettingsRepository(private val context: Context) {
         val countdownSeconds = intPreferencesKey("countdown_seconds")
         val forceAudioWithoutHeadphones = booleanPreferencesKey("force_audio_without_headphones")
         val showImmersiveProgressBar = booleanPreferencesKey("show_immersive_progress_bar")
+        val showImmersiveStopButton = booleanPreferencesKey("show_immersive_stop_button")
         val preferLowestRefreshRate = booleanPreferencesKey("prefer_lowest_refresh_rate")
         val monochromeFlashMode = booleanPreferencesKey("monochrome_flash_mode")
         val immersiveBrightnessPercent = intPreferencesKey("immersive_brightness_percent")
@@ -36,6 +37,7 @@ class SettingsRepository(private val context: Context) {
                 ?: 5,
             forceAudioWithoutHeadphones = p[Keys.forceAudioWithoutHeadphones] ?: false,
             showImmersiveProgressBar = p[Keys.showImmersiveProgressBar] ?: true,
+            showImmersiveStopButton = p[Keys.showImmersiveStopButton] ?: true,
             preferLowestRefreshRate = p[Keys.preferLowestRefreshRate] ?: true,
             monochromeFlashMode = p[Keys.monochromeFlashMode] ?: false,
             immersiveBrightnessPercent = (p[Keys.immersiveBrightnessPercent] ?: 50).coerceIn(5, 100),
@@ -58,6 +60,9 @@ class SettingsRepository(private val context: Context) {
             if (prefs[Keys.preferLowestRefreshRate] == null) {
                 prefs[Keys.preferLowestRefreshRate] = true
             }
+            if (prefs[Keys.showImmersiveStopButton] == null) {
+                prefs[Keys.showImmersiveStopButton] = true
+            }
         }
     }
 
@@ -80,6 +85,10 @@ class SettingsRepository(private val context: Context) {
         it[Keys.showImmersiveProgressBar] = value
     }
 
+    suspend fun updateShowImmersiveStopButton(value: Boolean) = context.dataStore.edit {
+        it[Keys.showImmersiveStopButton] = value
+    }
+
     suspend fun updatePreferLowestRefreshRate(value: Boolean) = context.dataStore.edit {
         it[Keys.preferLowestRefreshRate] = value
     }

app/src/main/java/com/mindmachine/mvp/domain/Models.kt

@@ -42,6 +42,7 @@ data class AppSettings(
     val countdownSeconds: Int = 5,
     val forceAudioWithoutHeadphones: Boolean = false,
     val showImmersiveProgressBar: Boolean = true,
+    val showImmersiveStopButton: Boolean = true,
     val preferLowestRefreshRate: Boolean = true,
     val monochromeFlashMode: Boolean = false,
     // Default used only before DataStore emits (and as a fallback).

app/src/main/java/com/mindmachine/mvp/session/MainViewModel.kt

@@ -304,6 +304,7 @@ class MainViewModel(
         settingsRepository.updateForceAudioWithoutHeadphones(value)
     }
     fun updateShowImmersiveProgressBar(value: Boolean) = viewModelScope.launch { settingsRepository.updateShowImmersiveProgressBar(value) }
+    fun updateShowImmersiveStopButton(value: Boolean) = viewModelScope.launch { settingsRepository.updateShowImmersiveStopButton(value) }
     fun updatePreferLowestRefreshRate(value: Boolean) = viewModelScope.launch { settingsRepository.updatePreferLowestRefreshRate(value) }
     fun updateMonochromeFlashMode(value: Boolean) = viewModelScope.launch { settingsRepository.updateMonochromeFlashMode(value) }
     fun updateImmersiveBrightnessPercent(value: Int) = viewModelScope.launch {