ENCRYPTABLES: Finish recrypt

[mtnstar]

Recrypt feature is implemented and can be merged soon: #625

Based on Luca's IPA: https://github.com/puzzle-bbt/docs/blob/master/ipa/2022-lbu/ipa.md

ToDo

• Study PR
• Rebase to current master
• Make it working
• Write tests
• Smoke Testing
  • Check file transfer
• Fix file transfer
  • Encrypt transferred encryptables on personal team click
  • Write tests for this
• Remove Crypto::Symmetric::Aes256 in transfer specs
• Sync with @mtnstar and add some additional tasks if needed
• Do extensive testing
• Update Version, Changelog
• Implement PR feedback
• Sync with UX for green lock icon
• Fix rubocop offense
• Implement new feedback
• Check for notification for file transfer

[lkleisa]

I start with taking the changes of Luca to a new branch #728. Now, there are some changes, which need more work, I will do that on Wednesday.

[lkleisa]

New tests are added, now smoke testing is needed on monday