Splitting spell casting into success/failure

[MahtraDR]

Whilst adding ETC to base spells in #5661 I noticed that in our cast-messages we include

- ^Your spell .*backfires
- You strain, but are too mentally fatigued

Both of which indicate the spell failed to cast.

The idea that came to me is to split these messages into success and failure messages, like we now have for cyclics, in common-arcana. Maybe even move the @@cyclic_release_success_patterns list from common-arcana to base-spells, and maintain all of this data in one file.

Thoughts?

[KatoakDR]

Yes, it would be helpful to have the prep and cast messages in base-spells separated into success and failure patterns. It would make common-arcana a bit nicer too because it has to list all the failure patterns in bput to handle a failure appropriately.

It is time for this to be updated to our newer coding style.

Thanks

[MahtraDR]

Would we have two arrays for success failures, or would we add success messages to spell entries themselves?