[Feature Request] Check snap for Preview Time

[dudehacker]

kinda minor thing but can you detect if preview time is snapped or not.

sometimes after audio change, cause offset shift and mapper forget to shift the preview by like 5-10ms

some mapper are perfectionist and will self DQ for this change:
https://osu.ppy.sh/beatmapsets/1696523/discussion/-/generalAll#/3141891

would be nice to add if not too much trouble.
can use warning, not problem, could be intentional unsnapped.

[Naxesss]

Warning for unsnapped preview times would yield too many false positives, as this generally isn't an issue, and it definitely wouldn't be a notable DQ if DQed for (or at least I hope not).

Ideally you'd want to tie this in with snapshots: If the uninherited line where the preview point existed was moved, and the preview point is now unsnapped, ask whether they forgot to move it. But no check currently ties in with snapshots and it seems a bit overkill to implement for this.

So will leave this to others to add as a custom check if they want it.