Take full advantage of object storages

[CarlSchwan]

When we are using an object store and not using server side encryption, Nextcloud clients (web/desktop/...) should do as many operation as possible directly on the object store without relying on Nextcloud. This is possible thanks to pre-signed links which allow to do some operation for a certain amount of time.

Must have (P0/S)

• Download files from S3 directly perf(s3): Provide direct pre-signed download link #54436
  • Support for desktop client
  • Support for web client
  • Support for iOS client
  • Support for Android client
• Download files from S3 to generate previews feat(previews): allow ffmpeg to connect direct for AWS S3 buckets #53634
• Download previews from S3 directly Un-authentificated previews loading using pre-signed urls #54622

Nice to have (P2/M)

• Upload files to S3 directly