WTH is it not possible to upload a snapshot?

Makes migrating and restoring a backup a lot easier.

Current:

  1. Download snapshot via HA
  2. Install SAMBA on new HA installation
  3. Browse to share
  4. Copy snapshot to a new instance
  5. Restore

Improved:

  1. Download snapshot via HA
  2. Upload via HA and restore

Also works great to restore offsite backups that do not exist anymore on the HA store, like with the Dropbox plugin that only keeps the X latest backups.

Duplicate of https://community.home-assistant.io/t/upload-a-snapshot-as-a-step-in-the-onboarding/219579