Feature/collection-thread-pool

This adds a new model for how we control threads when operating on collections. So any file audit/token audit/token registration will be controlled by the same source.

See merge request !1

This was done because we ended up with a lot of nesting of generics. While it's not too big of an issue, it became a bit less readable and overall just bloated lines.

Add fixes for manging collections between audit/token ingest threads