[Enhancement] Prevent Stacked Notes

[NotHyper-474]

What is this?

Inspired by a comment by Hundrec and the many issues about notes stacked on top of each other, this PR intends to add a way to prevent these pesky notes.

Current visualization of stacked/overlapped notes is below

To Do

• Visualization of stacked/overlapping notes.
• Prevent creation of stacked notes when pasting or dragging.

Suggestions are very welcome.

[AbnormalPoof]

I can see a warning being added, maybe with a button that allows you to see all instances of them? Something like CTRL+F in a web browser:

Though that's probably a bit out of scope...

[lemz1]

I'd personally just either have a check, which is done every time you paste, that removes all stacked notes, or if you want to a button that does it for you.
I don't see the reason for showing where stacked notes are, since you are going to remove them either way, right?

[Hundrec]

I'd say giving the charter the freedom to create stacked notes is important. Having an adjustable threshold for what constitutes as "stacked" (0-100ms, for example) could go a long way to enable that freedom

[AbnormalPoof]

since you are going to remove them either way, right?

Unless you're like making a spam/joke chart, then yeah maybe?

[lemz1]

I'd say giving the charter the freedom to create stacked notes is important. Having an adjustable threshold for what constitutes as "stacked" (0-100ms, for example) could go a long way to enable that freedom

I thought stacked meant exactly 0ms, but i guess it is nice to have a threshold for more control

[Hundrec]

I thought of having that customization feature because I've found that Funkin's chart editor would often place notes in an imprecise manner back in the legacy versions.
I haven't really trusted note placements to be millisecond-precise since then, so a slider would ensure any stacked notes not visible to the naked eye would be shown.

[NotHyper-474]

Finally, the messy commit history is no more. Thank god for rebase