Refactor of client mixin for PlayerSkinTexture, moving to a static class, and conditional mixins for different Minecraft versions.

New Custom Player Icon support (if black/white pixel set at 31, 49), uses certain empty UV coordinates in player skin file.

- Click Handler no longer plays sounds
- Moved sounds to ClientPackets, so all clients play nearby sounds from the Chat interactions. Sound gets quieter with distance (0 to 8 blocks)

- Broadcast this new playerId along with the chatData

Fixed entity heights for EnderDragon (lowered chat bubble) and fixed tilt calculation to use the padding above the entity height.

 when sending chunked lite JSON data to new player on server (i.e. someone reconnects or logins in).