Maps made by the mapset host in collaboration with other mapper(s) should be tagged as Collaboration instead of Guest Difficulty

[Nivalyx]

Related to the recent change that allows for multiple mappers to be assigned to one map, and was discussed briefly in #nat earlier.

As of now, the website considers everything that involves a non-hosting mapper (to any extent) as a "Guest Difficulty". This has caused inaccuracies on cases like this, where the mapset host is being tagged as part of this "Guest Difficulty" although the difficulty is technically theirs.

If any, I suppose these maps should instead be marked as something of a "collaboration difficulty" to reflect what they truly are.

[nanaya]

Currently the wordings on beatmap and score page is just "mapped by". I wonder if it should be made uniform.