[iamnbutler]

Fix-train task "Diff and pull request sidebar". Map ids ^692, ^710, with ^684 confirmed already fixed; ^633, ^738 and ^617 skipped (below).

• ^692: the details sidebar's summary stays clamped to four lines, with Show more / Show less shown only when the text doesn't fit (measured, so a short summary gets no button).
• ^710: the channel's pull request is read again when the window regains focus, so a PR closed or merged on GitHub drops Merge PR / Close PR as soon as the person comes back, instead of after the next 60 s poll.
• ^684: already fixed by fix(ui): drop Diff header totals that don't fit instead of running under the toolbar #596 (totals that don't fit wrap out of sight). Seen at 1280px with the details sidebar open, Update PR, Close PR and Open a lane's dev server from its channel #16 in the toolbar: the lane name and base stay visible and no total runs under the toolbar.

Not changed:

• ^633 React fix(app): add per-project channel creation in All Projects #185: not reproduced, again (development React build, five sends in agent mode with the Diff tab open behind Chat, in a split, and with the details sidebar open, including runs that changed files). Same result as fix(app): offer PR actions only when they can work, and say what GitHub and the terminal mean #587.
• ^738 / ^617: a channel continuing a PR works on its own lane branch (<channel>/<name>) and pushes to the PR's branch. Neither the sidebar's PR lookup nor the dashboard's Continue can see that link today, and lane push pushes to the lane's own branch name and resets its upstream, so tracking the PR branch as the lane's upstream doesn't hold. Making it work needs a decision on where a channel records the PR it continues (channel metadata vs. git upstream) and how Update PR pushes to it; left on the fix-queue item.

Smoke: isolated loopback host from this lane on port 5110 with Vite (development React) on 5111, own ACE_HOME, config and keychain service, headless Chromium. Summary: Show more appeared on a five-line summary and expanded it fully; Show less clamped it again. PR: on githubnext/ace-testbed#16 (opened by the channel's agent for this test), with the sidebar showing Close PR, gh pr close 16 left Close PR shown 4 s later with no focus change; a window focus event then showed the closed PR and Create PR within 4 s. bun types and bun run ci pass.

Built in Ace

No. Built by Claude Code as a fix-train worker for the ace-map review, because the train runs outside an Ace channel; smoke tests drove the web app with headless Playwright. Dogfooding gap tracked in #5.