Replace 0 (merged), 1 (global) and 2 (character) with an representive enum.
Check items against exclude rules if AUTO_PICKUP_ZERO is enabled.
Merge remote-tracking branch 'dda/pr/8182' into dda-master

* dda/pr/8182:
  Check items against exclude rules if AUTO_PICKUP_ZERO is enabled.
  Replace 0 (merged), 1 (global) and 2 (character) with an representive enum.