Standarize file names

>OK that was going to be my next proposal, but I thought I would separate the two issues.

Makes sense! Going to accept+pull, and we can take the conversation over there for the next.

> I was thinking problems to be p_\d+.pddl or p_\d+_d+.pddl etc (sometimes we want 2 numbers) and then domains to be d_\d+.pddl , etc or just domain.pddl if shared...

I was thinking perhaps a mapping file? There will be domains with 3 #'s, 4 #'s, etc, etc. But a dedicated file that lists how each problem was generated (grid size, agent carry capacity, dungeon depth, etc, etc) could let us go from the `p_\d+.pddl` to the actual details. Ideally it's also in the problem PDDL as comments, but that's not always followed...

What are your thoughts on `p01.pddl` -vs- `p1.pddl`?

_Originally posted by @haz in https://github.com/AI-Planning/fond-domains/issues/2#issuecomment-2296594627_