Visual cooldown — timer display directly on the object, updating in real time.
Placement of shalkers — Shift+PCM for installation on the ground.
Ready Notifications — the message "✓ Ready to open!" after the cooldown.
critical performance issues
Unmanaged BukkitRunnable tasks created memory leaks
Create new scheduler tasks with each click in the inventory
Inefficient verification of the type of material through string operations
Re-reading the configuration file at each event
Added the stopAllCountdowns() call in the on disable method
The bug has been completely fixed - items are now saved correctly when placing the storage boxes via Shift+PCM.