Implements automatic OS upgrade functionality for Podman machines that requires no user input beyond running the command. The upgrade logic automatically determines the appropriate upgrade path using a three-way comparison between client version, machine version, and OCI registry:
* When the client version is older than the machine version, no action is taken and an error is returned.
* When the client version matches the machine version, the OCI registry is queried to check for in-band updates by comparing image digests. This handles minor, patch level, and updates oci image use cases.
* When the client version is newer than the machine version, the machine is upgraded to match the client's major.minor version.
* No manual image selection or version specification required.
The command supports dry-run mode and JSON (only) output format for automation.
Signed-off-by: Brent Baude <bbaude@redhat.com>
aba2df7517