Release v0.5.0

Major update!

Two-host support — pair one device with two computers and switch between them with a fingerprint.

Added

• Register a second host with fingerprint + device button (two-step, no shared secret to type).
• Switch fingerprint (slot 5) hands the device to the other host — each slot advertises its own BLE identity.
• Cross-slot unpair clears the other host and rotates that slot's BLE address so it won't auto-reconnect.
• TUI Hosts panel (H menu) and slot CLI commands — status, per-slot unpair, and a separate whole-device factory-reset.

Fixed

• unpair no longer deadlocks when parked on an unpaired slot; misleading wording corrected.
• Pairing progress hardened; no more startup black screen; Hosts panel survives transient BLE hiccups.
• TUI aligned with the CLI (u confirms, pairing matches exactly).