multi-time-point multi-channel issues

Hi @jni,

just a brief placeholder for something that I noticed today.

When using a dataset with channel order (c,y,x) and 3 channels, napari loads this as if it was a time-series or Z-stack.
After clicking 3 points with affinder I noticed that it didn't switch to the other layer. After clicking a 4th point it crashed.
Looking at the error message I interpret the behaviour as affinder thinking it needs to align volumes or some other dimension misinterpretation.

As some users may want to register a single frame to a time series, or several multi-channel time-series on top of each other
the interpretation of the dimension becomes important. I heard there is a guardian of dimensions keeping an eye on such matters.

Can try and create a more detailed report in the coming days, but I guess as affinder is still WIP maybe this is already on your radar.

Reproduce the issue with a dataset ordered as (c,y,x) and three channels, then annotate three and four points with affinder while observing layer switching and the crash. Start from the resulting error message and dimension interpretation; done means multi-channel and multi-time-point data are distinguished correctly and the reported interaction no longer crashes.

Written by the indexing model from the issue text.