Save original int map ID if conversion is lossy

[roccodev]

In 1.13+, map IDs are no longer encoded in the item damage, so their maximum value was bumped to the 32 bit limit.

This PR makes it so, when going 1.13->1.12 and if the original map has an ID too large:

• The original ID is still kept in the map nbt tag
• The damage value wraps around 32767. Previously, the short cast would make it so every map ID mapped to a negative short value would use a damage value of 0, which would make the client cache them under the same key. Note that maps with an ID distance of >32767 might still conflict, but this is better than before.