Remaining issues from repo change

[Thaewyn]

• Make sure player attacks can also apply statuses to enemies
• Check all server routes for things like res.status(500) that don't actually work the way we want.
• Investigate and confirm how Defense decays in combat.
• update database schema so that guest users work (set userId to DEFAULT NULL instead of NOT NULL)
• Create theme selector
• Remaining combat phases: finish status effects, handle enemy attacks #19
• Create a handler for 'relics'
• Create a 'combat turn log'