UI: shorten positioning bullets + make guidance screen scrollable

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

@@ -830,11 +830,13 @@ fun SettingsScreen(vm: MainViewModel) {
 
 @Composable
 fun PositioningScreen() {
+    val scrollState = rememberScrollState()
     Column(
         Modifier
             .fillMaxSize()
             .background(MaterialTheme.colorScheme.background)
             .safeDrawingPadding()
+            .verticalScroll(scrollState)
             .padding(16.dp),
         verticalArrangement = Arrangement.spacedBy(8.dp)
     ) {
@@ -852,8 +854,6 @@ fun PositioningScreen() {
 
         Text("• Lie on your back in a safe, comfortable place.", color = MaterialTheme.colorScheme.onBackground)
         Text("• Rest the phone across the upper nose/forehead area so it stays stable.", color = MaterialTheme.colorScheme.onBackground)
-        Text("• Keep your eyes closed during immersive visual sessions.", color = MaterialTheme.colorScheme.onBackground)
-        Text("• Ensure comfortable breathing/airflow and stop if you feel discomfort.", color = MaterialTheme.colorScheme.onBackground)
 
         Spacer(Modifier.height(12.dp))
         Text("Disclaimer", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onBackground)