Variable backpack capacity #10
Description
The number of slots in a the inventory should not be limited to 20. Better backpacks should be able to hold more items.
In practice this would require:
- Introducing a new equipment slot for the backpack, which cannot be empty (a default basic backpack would be always equipped unless a better one is equipped)
- Taking into account the currently equipped backpack when computing maximum capacity
- Handling edge cases (e.g. dealing with item surplus when equipping a lower-capacity backpack)