The recent changes related to adding support for working beatmap load
cancellation exposed a flaw in the beatmap difficulty cache. With the
way the difficulty computation logic was written, any error in the
calculation process (including beatmap load timeout, or cancellation)
would result in a 0.00 star rating being permanently cached in memory
for the given beatmap.
To resolve, change the difficulty cache's return type to nullable.
In failure scenarios, `null` is returned, rather than
`default(StarDifficulty)` as done previously.
I am aware there are more throughout the codebase but intentionally left
the remaining mentioned for one reason or another. The intention here is
to mainly change user-facing versioning to change the positioning of the
"lazer" term (to be where we would expect "cuttingedge" or "beta" to
be).
This reverts commit f3faad74d5, reversing
changes made to 712e7bc7bf.
Several issues arose after migrating to 5.0, including, but possibly not
limited to, performance regressions in song select, as well as failures
when attempting to save beatmaps after metadata changes in the editor.