Bag: hint and Clear selection stay visible under the list (t20)

The hint and Clear button were inside the scrolling bag list, so a long
Ctrl list scrolled them away. They now sit in a footer under the list, and
Clear is a full-width, highlighted "Clear selection" button.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/agent-log.md

@@ -4,6 +4,14 @@ What agents have done, newest first. Add an entry for every piece of work: the d
 note or request it was for, what changed, the files touched, the tests run, and anything left
 open or not verified. Keep each entry short; the git history has the details.
 
+## 2026-10-24: t20 follow-up: bag hint and Clear stay visible (Claude Code)
+
+- The hint and Clear were inside the scrolling `#baglist`, so a long Ctrl list scrolled them away.
+  They now render into a new `#bagfoot` under the list (`src/shell.html`, `renderBag`); Clear is a
+  full-width, highlighted "Clear selection" button (`style.css`).
+- `test/play.py`: a long Ctrl list scrolls while the hint and a full-width Clear stay visible.
+  Screenshots `shots/t20c-ctrl{,-900}.png`. Tests: `run_all.py --browser` all passed (play.py 232).
+
 ## 2026-10-24: t20 follow-ups: deselect when blown out, Ctrl + wheel, Ctrl+click (Claude Code)
 
 - Blowing the last of a selected material removes it from the selection (`toolTick`); materials