Improve romm output token

[mainrs]

Is your feature request related to a problem?

Romm expects the data to be present in two formats:

https://github.com/rommapp/romm?tab=readme-ov-file#folder-structure

However, the current output token is only capable of producing the library/roms folder of structure A. This is the case if one specifically asks igir to output to libbrary/roms/{romm}.

Describe the solution you'd like

It would be great if the token would work in such a way that it puts all roms into library/roms and all bios files into library/bios when specifying the output library/{romm}.

Additional context

One could think about adding rommA and rommB as alternatives to the current one, keeping backwards compatibility.

[emmercm]

If I understand it right, for "Structure B" you'd want to run Igir with two different sets of options:

igir \
... \
--output "library/{romm}/roms" \
--no-bios

and

igir \
... \
--output "library/{romm}/bios" \
--only-bios

I think you would need to do something similar for "Structure A" as well. I'm hesitant to make any changes because the current token should allow for both formats.

Thoughts?