Actual Flowrate Visualization of some kind

[Auturistic]

Hello, basically the current flowrate visualization in the slicer can cause confusion because it does not take into account move speed which the slicer often changes while keeping the flow constant... which increases the actual flowrate but that does not show up in the previews.

There's this whole discussion which shows up the confusion that, at the very least, I had:
#7422

Yes, I know I did a dumb and didn't realize something but introducing something like this would have prevented my and others' confusion.

Turns out it could still be related to a bug but the idea stands.