transforms: (convert_stream_to_snax_stream) split up layout resolution pass

[jorendumoulin]

situation before this pr:

stream.streaming_region
 --> autoflow-scheduler-pattern
stream.schedule_op
 --> layout_resolution-pattern
snax_stream.streaming_region

The layout resolution includes a lot of gemmx specific hacks entagled between the logic of layout resolution, which is not nice. To keep everything clear this should be separated somewhat. This also makes it fit the mathematical model behind the passes more cleanly.

Therefore this pr splits it up into:

stream.streaming_region
 --> autoflow-scheduler-pattern
stream.schedule_op
 --> layout_resolution-pattern
stream.access_pattern_op
 --> convert_stream_to_snax_stream-pattern
snax_stream.streaming_region

This PR doesn't change any logic, just separates it into two.

[JosseVanDelm]

Very nice PR, but I think this requires a bit more granular testing and a bit more comments overall

[JosseVanDelm]

The direction this is heading in is very exciting! Thanks @jorendumoulin!

Thank you for the extra docstrings!

nit: There's another one docstring missing though

I think it might make sense to split the testing for these passes up later down the line, but I agree that is not the main goal of this PR :)