fix: size the pending-changes dialog to its content

380px of dialog for three rows left most of itself empty. The height is
asked of the layout now, capped so a long list scrolls rather than growing
past the screen and floored so a single row does not collapse it.

A background role on the scroll viewport was tried in the same pass and
reverted: the dialog renders semi-transparent under the developer's
compositor, and painting a Base-coloured layer under the list made that
worse rather than better. The transparency is the desktop's own doing, which
is the trap this project has already recorded for window geometry.

Not covered by a test. The offscreen platform returns an identical frame for
a correct size and a broken one, so an assertion there would pass against
both; CLAUDE.md records that measurement. Confirmed by hand instead.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01P88Q3MCSCSQxKDy7pmXh9F

0 files changed, 0 insertions, 0 deletions