The purpose of this ticket is to separate the 3 types of refresh that can happen in the catalog cache given a shard version:

• Chunk change: will only get changed chunks
• Index change: will only get changed indexes
• Full change: Full refresh, will get chunks and indexes

The intention of this ticket is to not penalize chunk refreshes (which will be expected to be more frequent than index refreshes) by querying another collection (the index collection) unless it is necessary.