Read a timeout in units, share one usage answer, and let a tilde mean home

The composer's settings row is outlined bubbles opening round menus, and
the message box is a TextFieldValue so anything put into it without being
typed -- a draft, a share, a slash command -- leaves the cursor at the end.

A tap that puts a text selection away no longer also collapses the card the
text was drawn in: every open and close on the session screen goes through
one guard that spends such a press on the selection.

The usage bar and the usage dialog were two polls of one measurement and
disagreed for up to a minute at a time; they are one feed now, and the
countdown rounds up to the minute in the one place both read.

A working directory typed as ~/repos/ai-app was four literal characters on
the local transport and as an argument on both, so the existence check
refused every home-relative path. It is checked by entering the directory
now, expanded for a local spawn the way the remote shell expands it, and
stored short so the phone draws what somebody would write.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

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

@@ -0,0 +1,54 @@
+package com.example.aiapp
+
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Shape
+import androidx.compose.ui.unit.dp
+
+// The composer's row of settings and pickers, and the menus they open. One file because the
+// outline and the corner are one appearance: a control shaped like this opens a surface shaped
+// like this, and a reader learns the pair once.
+
+/**
+ * A bordered pill: a control that can be seen without being pressed.
+ *
+ * The composer's row -- attach, model, permission mode -- was text buttons, which draw nothing at
+ * all until they are touched. Three bare words sitting under the message field read as a caption
+ * about the field rather than as three things to press, and the only way to find out otherwise was
+ * to press one. The outline says "control" without the weight of a filled button, which is reserved
+ * here for the two that act on the session (send, and start/stop).
+ */
+@Composable
+fun BubbleButton(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    content: @Composable () -> Unit,
+) {
+    OutlinedButton(
+        onClick = onClick,
+        enabled = enabled,
+        shape = BubbleShape,
+        // A text button's padding rather than a filled button's 24dp: these sit three across
+        // under the message field, and the wider padding is what decides whether the row fits.
+        contentPadding = ButtonDefaults.TextButtonContentPadding,
+        modifier = modifier,
+    ) {
+        content()
+    }
+}
+
+/** Fully round ends, so the control reads as a bubble rather than as a box. */
+val BubbleShape: Shape = RoundedCornerShape(percent = 50)
+
+/**
+ * The corner on a menu one of these opens.
+ *
+ * A radius rather than [BubbleShape]'s half-height: a menu is as tall as its options, and rounding
+ * ends that tall would bow its sides. This is the roundest corner that still leaves a straight edge
+ * beside a one-line option, which is the shortest menu here.
+ */
+val BubbleMenuShape: Shape = RoundedCornerShape(20.dp)