fix: drop gear weapons when their station furniture is gone - #29

Summary

• Tag each gear-station weapon display and remember its id, so a restart removes the previous display instead of leaving another one floating.
• When a saved station's furniture barrier is gone, on load or chunk load, drop the weapon once and delete the station record. A barrier that is still there keeps the weapon, so a lookup miss cannot throw crafts away.
• If a magic-station break is not cancelled, drop that station's weapon. Breaks of a station that still holds a weapon stay cancelled, matched to the furniture's own block.

Existing displays that are no longer in gear-stations.yml are left for manual removal.

Test plan

• Dev build succeeds
• Prepare a weapon on a magic station, restart the plugin, and confirm a single display is still on the station
• Break the station furniture out of band and confirm the weapon drops and the display is gone
• Shift-left-click abort still refunds and does not break the furniture

Made with Cursor

Summary by CodeRabbit

• Bug Fixes
  • Improved protection for occupied stations and stations recently involved in an aborted session when nearby furniture is broken.
  • Station state is now checked as chunks load, helping remove stale displays and recover weapons when station furniture is missing.
  • Displays associated with stations are cleaned up when the server shuts down.