mutable/immutable version of SerializedItem
SerializedMetaAccess & MapAccessUtil to access item data
deep copy of item in SerializedItem constructor
SerializedItem hash code & key hash code impl for faster comparison
ignoring top inventory (due to items sometimes disappearing)
fixed nbt compound falsely identified invalid item stack as item statck
fixed game mode switch causing fake edits to become real edits
fixed picked up items sometimes disappearing