Community contribution from @ChrisChrome (tested on Debian 13 headless). Adds scripts/debian-13-setup.sh — server/player/both modes, systemd units, kiosk autologin, and management scripts (status/update/logs) — modeled on the Raspberry Pi setup. Also fixes Chromium fullscreen by detecting screen resolution at runtime (replacing --start-fullscreen), applied to both the Debian and Pi scripts, plus a README entry.
Maintainer review fix: the kiosk wait-loop now polls /api/status (the server's real readiness endpoint) instead of the non-existent /api/health, which had been silently burning the ~120s timeout on every all-in-one boot (bug inherited from the Pi script, fixed in both).
