[Interaction] "Community service" quest minor cleanup

[Xaver-DaRed]

I affirm:

• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

As title sais. No real logic changes were made.

• Changed some npc variables to be zone variables. For consistency more than for anything else.
• Simplified functions to use less parameters.
• Created a few global functions to call the quest logic from the zone script. The purpose for this is:
  • Have as much logic as possible centralized inside the quest script.
  • Have ALL variables used by the quest inside the quest script.
• Changed a quest variable handling to be more clear.

Steps to test these changes

None. This isnt supposed to break nor fix anything.