Create a Minecraft Paper plugin (API version 1.21) with the following behavior: CORE MECHANIC: - When a player is killed by another player (PvP only), the victim drops their player head. - If the player dies from any other cause (fall, mob, lava, etc.), nothing happens. HEAD SYSTEM: - The dropped head must be a PLAYER_HEAD with the correct skin of the victim. - Store the victim's UUID inside the head using PersistentDataContainer (NBT). - The head must be uniquely identifiable as a "HeadBan" head. BAN SYSTEM: - When the player dies (killed by another player), they are banned for 1 hour. - The ban message should say: "You are banned until your head is placed or 1 hour passes." - The player should be kicked immediately after death. UNBAN CONDITIONS: - If someone places the head block, the banned player is immediately unbanned. - Broadcast a message: "<player> has been unbanned!" HEAD PROTECTION: The special head must be protected in ALL of the following ways: - It must NOT despawn (