Efficient crowdaction listing

[rubenhorn]

⚠ Partial research task ⚠

1. Fetch list of crowdactions more efficiently by including the status (joinable/upcoming/ended) in the partition key to overfetching and filtering.
2. Consider archiving the completed crowdactions and deleting them from the database. (If they should still be accessible, consider using static assets in S3 or other alternatives)