Verify real-phone use and address mobile gaps #18

Checked only in Chrome's iPhone emulation, not on a real phone. Terminals have no Esc/Ctrl/arrow key row, so they're limited to typing commands. Diffs scroll sideways on long lines. Chrome asks for local-network permission before the deployed web app can reach a host (Safari doesn't). Push notifications need HTTPS and a service worker.

Tracked by #58. Migrated from TODO.md — During dogfooding.