[Magiclysm] Fix demonic possession causing starvation penalties

[SariusSkelrets]

Summary

Mods "[Magiclysm] Fix demonic possession causing starvation penalties"

Purpose of change

The blood mage's demonic possession grants huge size but didn't change calories, making what is supposed to be a buff mostly cause penalties from not having enough calories for your size

Describe the solution

Add a EOC that changes the calories that runs as the spell is casted. The player-visible spells triggers the EOC that changes the calories and cast the real spell.
Also use a demon version of HUGE_OK to use the temporary shapeshifting flags.

Describe alternatives you've considered

Testing

Used demonic possession without the fix on a starting character: goes from overweight to emaciated

Used demonic possession with the fix on a starting character: starts at overweight, stays at overweight

Additional context