Belay 1.3.1

The statistics chart learned to answer the cursor, and Pi joined the presets.

📊 The chart follows your cursor. Hover over a day in Statistics and the bar lifts while the figures above switch to that day. Move away and the totals come back.

🔌 Pi is built in. One click in Settings starts watching Pi's sessions. Added after a request in #3.

🔇 Quiet sessions stay quiet. If an agent stops mid-answer, Belay now says it went quiet instead of calling the run finished.

💻 Closed-lid stops explain themselves. If the time limit or heat protection ends a closed-lid hold, the notification tells you why. Direct builds.

✨ Also: the helper status in Settings updates as soon as you approve it, Belay launched mid-run picks the run up right away, and failed update checks now say why in the log.

Details in the changelog.