Adjusted catalog importer to not delete everything when importing. It now updates the items instead.
Removed the doubled catalog json, now `storage/app/catalog/catalog.json` is the only true catalog source.
Implemented tracking the progress of Signature challenges.
Also implemented both challenges Endpoints "getChallenges" ans "getChallengeProgressionBatch".
For "getChallenges", we just return an empty array since we dont need weekly and dailies yet.
Also update updateMetadatagroup to only update picked challenges when to challenge already exists for that item.
Updated the import-catalog command to also import the signature challenges and associate them with the items that want them.
