Feature request: unpin / remove tracked PRs from the CI monitoring panel

Summary

The CI monitoring panel (above the prompt input, shows pinned PRs with branch name + CI status badge) does not expose any way to unpin or remove individual PRs from the list. Old merged PRs stay pinned indefinitely with no UI affordance to clean them up.

Reproduction

1. Track a PR (the panel pins it automatically when an agent/session interacts with a PR).
2. The PR gets merged and closed — but it remains in the pinned list.
3. Right-click / hover / open the side panel ("Monitoraggio CI" in Italian locale): no "remove", "unpin", or "✕" option appears next to individual PR rows. Only global toggles ("Correggi automaticamente CI e rispondi ai commenti", "Unione automatica quando pronto") and a link "Impostazioni di archiviazione automatica".
4. After several weeks of work, the list accumulates many stale merged PRs (in my case PRs from 2+ weeks ago, e.g. #63, #64 of my project, still pinned even though they are MERGED and closed). "Mostra altri 10" link reveals 10+ more.

Expected behavior

• Per-row ✕ / "Unpin" / "Remove from list" action.
• Optional: automatic cleanup of PRs in MERGED / CLOSED state after N days, configurable.
• Optional: bulk "Clear all merged" button.

Workarounds attempted

• Closing and reopening Claude Code: pinned PRs persist.
• Checking git worktree list / filesystem: PRs are not backed by worktrees, they're a UI-only tracking list.
• No CLI command or settings.json key seems to control this.

Environment

• Claude Code with Opus 4.7 1M (Media)
• macOS
• Locale: it-IT (panel labeled "Monitoraggio CI")

Impact

The panel becomes noisy and loses its usefulness for tracking currently-active PRs after a few weeks of normal usage.