Small changes incl. Single-item crafting

- Added a couple skill achievements as well as quest completion achievements
- Slightly improved skill deduplication logic
- Changed default male NPC voice type to Ghostface because Rocket was too annoying (Rocket is now the default for enemies)
- Added single-item crafting, e.g. cooking a raw salmon over a campfire to become smoked salmon. Single-item crafting works slightly different from multi-item crafting: The tier and rarity will always be the same as the ingredient, and the level will increase by 1 unless it’s already at the area level.