refactor: Move temperature data to bodypart

[Coolthulhu]

Checklist

Required

• I wrote the PR title in conventional commit format.
• I ran the code formatter.
• I linked any relevant issues using github keyword syntax so it can be closed automatically.
• I have committed my changes to new branch that isn't main so it won't cause conflict when updating main branch later.

Optional

Purpose of change

Move temperature data from character to body part to allow non-static body part count.

Describe the solution

Body part gets getters and setters for: temp_cur, temp_conv, frostbite timer.

• Handle saves with old temperature format

Describe alternatives you've considered

Testing

• Tests pass
• Running the game doesn't result in debugmsgs every turn

Additional context