Here we use `IHasColumn` to support rulesets with columns, and so I moved that interface out into `osu.Game` from `osu.Game.Rulesets.Mania`.
We also use the same threshold as the unsnap check to ensure that no problems slip through. Specifically where an object is simultaneously not concurrent and not unsnapped but still on the same tick.
Further separates them from `IBeatSnapProvider`'s `SnapTime`, and groups them together more, to prevent confusion between the two interfaces.
Also changes the xmldoc of the reference time to that of `IBeatSnapProvider` for consistency.
Seems `EditorBeatmap` already implements a different kind of `SnapTime` from `IBeatSnapProvider`, so method names here aren't great.
This is very similar to what https://github.com/ppy/osu/pull/12558 is doing, so may need to do some duplicate resolution later, especially surrounding `ClosestBeatSnapDivisor`.
Worth noting that this change makes 1/7, 1/5, etc unsupported for now, as we now rely on `BindableBeatDivisor.VALID_DIVISORS`.
This is different from the working beatmap's `.Beatmap` property in that it is mutated by the ruleset/editor.
So hit objects, for example, are actually of type `Slider` and such instead of the legacy `ConvertSlider`.
This should be preferred over `workingBeatmap.Beatmap`.
This allows us to use the same method of checking for other files that should exist, for example the audio file.
By using the same method, they all share test cases too.
Makes use of the new `BeatmapSet.GetPathForFile` method and removes dependency on `WorkingBeatmap` specifically, allowing us to switch to `IWorkingBeatmap` later.
This lets us access things like the background, track, etc. which are necessary for quality and filesize checks.
Also improves the structure of the `CheckBackgroundTest` class in the process.
We're probably not going to need GeneralChecks or BeatmapsetChecks.
The verify tab is only available to a single difficulty at a time, and we already have access to the rest of the set through `IBeatmap`.
