original: x86pup/conduwuit#93

TLDR

Tuwunel currently stores large media files by itself, we need to add a way to be able to use an S3 compatible store to store large media files in. It could potentially lessen the load in environments that support it.

S3 compatible stores support returning links for files which we could use to delegate the handling of files when it is supported.

Tasks after this

Implement migration from static store to S3 compat store.
Implement migration from S3 to static store.