As documented at https://github.com/git-lfs/git-lfs/blob/main/docs/proposals/ssh_adapter.md#requests-to-transfer-objects, the `upload` operation handles sending objects from the client to the server. Once the `upload` operation is implemented, the `put-object` an `verify-object` commands need to be implemented as described at https://github.com/git-lfs/git-lfs/blob/main/docs/proposals/ssh_adapter.md#uploads which is being handled with https://gitlab.com/gitlab-org/gitlab-shell/-/issues/756+ and https://gitlab.com/gitlab-org/gitlab-shell/-/issues/755+ respectively.