The "Working — message will queue" strip lived inside the sized input Pane, so
appearing/disappearing ate the textarea's fixed height and clipped it, forcing
a resize. Move it into the message Pane alongside the connection/error banners
— those correctly consume transcript space (flex-1) rather than the input's
fixed height. The input Pane is now stable whether or not a background turn is
running. Styling/idiom unchanged.
VERSION: 0.17.2 -> 0.17.3
dtoro
058f1afcdc