Don't re-encrypt all encrypted docs on a password change

[Terreii]

Is your feature request related to a problem? Please describe.
Whenever the crypto-password is changed, all encrypted documents are re-encrypted!

Describe the solution you'd like
Generate a internal password on every password change (and the setup). And use this internal password to encrypt documents. The new internal password and all old ones can be stored in documents that are then encrypted in the users crypto-password.

Describe alternatives you've considered
The current implementation works fine but takes up much space on the server and over the network.

Additional context
The biggest problem lies in syncing. In the old implementation, the user could be asked for the old password and the old salt could be gathered from the salt-doc history.
Also any internal password would have to have an id (UUID from hoodie on add?). And every document that is encrypted with this password would also store that id.