Improve custom autotiler specificity

### I am planning on implementing this myself

No

### Describe your request

Currently there is a lack of specificity detection thus priority order within custom mask ids of the blacklist or whitelist type; in reality, masks may be more or less specific than one another within each group. If reasonable this should be accounted for.

### Additional context

https://github.com/EverestAPI/Everest/blob/dev/Celeste.Mod.mm/Patches/Autotiler.cs#L171-L172