Pin the transcript to its tail, and stop asking about every command

**The scroll.** The transcript scrolled on new items and nothing else,
which missed the two cases that matter most. An imported session's history
arrived and left the view wherever it landed; the keyboard opening shrank
the viewport and slid the newest messages under the IME, so typing meant
typing into a view showing the middle of something.

The view is now pinned to the tail, and it is the reader's scroll that
decides: settling anywhere above the bottom releases the pin, settling
back at the bottom re-arms it. The pin is written only when a scroll
*ends*, so it survives the moment when new content has just pushed the
bottom away but the reader never moved -- deriving it continuously from
"is the bottom visible" would release it on every append, which is the
race that makes naive follow-the-tail implementations let go at random.
New items and viewport resizes both re-scroll; the jump is instant rather
than animated, because an imported session appends hundreds of items at
once and animating through them is a light show.

**The input field gets a row of its own**, above the buttons. Sharing one
row put the full width behind three controls, so the thing being typed
into was the narrowest thing on the row.

**Permissions default to auto, and importing can choose.** The spawn
screen defaulted to "manual" and imports passed no mode at all, so the
CLI asked about everything -- and on a phone every ask is a round trip to
a question card, which is how "allow Bash?" became the most-answered
question in the app. Both paths now default to auto, with the other modes
one tap away for a session that warrants caution.

Looked at running, all three: an imported session opens at its bottom,
the tail stays visible while typing with the keyboard open, and the mode
picker shows auto selected.

app/androidApp/src/main/kotlin/com/example/aiapp/ImportScreen.kt

@@ -56,6 +56,9 @@ fun ImportScreen(
     // Deleting a transcript cannot be undone, so it is asked rather than done. Held as the row
     // itself, not a flag, so the dialog can say which session it is about.
     var confirming by remember { mutableStateOf<Importable?>(null) }
+    // Same default as the spawn screen, and for the same reason: a phone
+    // is the wrong place to answer "allow Bash?" forty times.
+    var permissionMode by remember { mutableStateOf("auto") }
 
     fun loadSessions(setup: Setup) {
         sessions = LoadState.Loading
@@ -134,6 +137,13 @@ fun ImportScreen(
                         color = MaterialTheme.colorScheme.onSurfaceVariant,
                     )
                 } else {
+                    ChipGroup(
+                        label = "Permissions",
+                        options = listOf("manual", "acceptEdits", "auto", "bypassPermissions"),
+                        selected = permissionMode,
+                        onSelect = { permissionMode = it },
+                    )
+                    Spacer(Modifier.height(8.dp))
                     failure?.let {
                         Text(it, color = MaterialTheme.colorScheme.error)
                         Spacer(Modifier.height(8.dp))
@@ -156,6 +166,7 @@ fun ImportScreen(
                                                 setup = setup.id,
                                                 provider = useProvider.name,
                                                 title = "",
+                                                permissionMode = permissionMode,
                                                 import = session.id,
                                             )
                                         }

app/androidApp/src/main/kotlin/com/example/aiapp/SessionScreen.kt

@@ -38,6 +38,7 @@ import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.setValue
+import androidx.compose.runtime.snapshotFlow
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.ImageBitmap
@@ -187,8 +188,27 @@ fun SessionScreen(
     // closing the stream is what unblocks it when this screen goes away.
     DisposableEffect(summary.id) { onDispose { activeStream.get()?.close() } }
 
-    LaunchedEffect(items.size) {
-        if (items.isNotEmpty()) listState.animateScrollToItem(items.size - 1)
+    // Whether the view is pinned to the newest item. It is the reader's
+    // scroll that decides: settling anywhere above the bottom releases it,
+    // settling back at the bottom re-arms it. Written only when a scroll
+    // *ends* so that the pin's state survives the moments when new content
+    // has just pushed the bottom away but the reader never moved.
+    var followTail by remember { mutableStateOf(true) }
+    LaunchedEffect(listState) {
+        snapshotFlow { listState.isScrollInProgress }
+            .collect { scrolling -> if (!scrolling) followTail = !listState.canScrollForward }
+    }
+    // Two things move the bottom out from under the reader: a new item,
+    // and the viewport shrinking when the keyboard opens. Watching only
+    // item count handled the first and left the input box typing into a
+    // view whose tail had slid under the IME. `scrollToItem` rather than
+    // animated: on an imported session hundreds of items arrive at once,
+    // and animating through them is a light show, not scrolling.
+    LaunchedEffect(listState) {
+        snapshotFlow { items.size to listState.layoutInfo.viewportSize.height }
+            .collect { (count, _) ->
+                if (followTail && count > 0) listState.scrollToItem(count - 1)
+            }
     }
 
     fun act(action: () -> Unit) {
@@ -322,29 +342,36 @@ fun SessionScreen(
         // Always enabled -- a send while the session is running becomes a
         // steering message injected at the next tool boundary, which is
         // the point of the whole app.
-        Row(
-            verticalAlignment = Alignment.CenterVertically,
-            modifier = Modifier.fillMaxWidth().padding(8.dp),
-        ) {
-            TextButton(
-                onClick = {
-                    pickImage.launch(
-                        PickVisualMediaRequest(ActivityResultContracts.PickVisualMedia.ImageOnly)
-                    )
-                }
-            ) {
-                Text(if (pendingAttachments.isEmpty()) "+" else "+${pendingAttachments.size}")
-            }
+        //
+        // The field gets a row of its own, above the buttons: sharing one
+        // put the full width behind three controls, so the thing being
+        // typed into was the narrowest thing on the row.
+        Column(Modifier.fillMaxWidth().padding(8.dp)) {
             OutlinedTextField(
                 value = input,
                 onValueChange = { input = it },
-                modifier = Modifier.weight(1f),
+                modifier = Modifier.fillMaxWidth(),
                 placeholder = {
                     Text(if (pendingAttachments.isEmpty()) "Message" else "Message (+image)")
                 },
                 maxLines = 4,
             )
-            Spacer(Modifier.width(8.dp))
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                modifier = Modifier.fillMaxWidth(),
+            ) {
+                TextButton(
+                    onClick = {
+                        pickImage.launch(
+                            PickVisualMediaRequest(
+                                ActivityResultContracts.PickVisualMedia.ImageOnly
+                            )
+                        )
+                    }
+                ) {
+                    Text(if (pendingAttachments.isEmpty()) "+" else "+${pendingAttachments.size}")
+                }
+                Spacer(Modifier.weight(1f))
                 if (status == "running" || status == "compacting") {
                     OutlinedButton(onClick = { act { interruptSession(settings, summary.id) } }) {
                         Text("Stop")
@@ -354,6 +381,7 @@ fun SessionScreen(
                 Button(onClick = { send() }) { Text("Send") }
             }
         }
+    }
 }
 
 /**

app/androidApp/src/main/kotlin/com/example/aiapp/SpawnScreen.kt

@@ -67,7 +67,11 @@ fun SpawnScreen(
     var title by remember { mutableStateOf("") }
     var model by remember { mutableStateOf("") }
     var cwd by remember { mutableStateOf("") }
-    var permissionMode by remember { mutableStateOf("manual") }
+    // "auto" rather than "manual": on a phone every ask is a round trip to
+    // a question card, and answering "allow Bash?" dozens of times per task
+    // is what this app exists to avoid. Manual stays one tap away for a
+    // session that warrants it.
+    var permissionMode by remember { mutableStateOf("auto") }
     var busy by remember { mutableStateOf(false) }
     // Only the spawn's own failure. The fetch's lives in `options`: this
     // one leaves a filled-in form worth keeping, and that one leaves
@@ -338,7 +342,7 @@ fun SpawnScreen(
  */
 @OptIn(ExperimentalLayoutApi::class)
 @Composable
-private fun ChipGroup(
+fun ChipGroup(
     label: String,
     options: List<String>,
     selected: String?,