This commit implements automatic creation timestamp functionality for artifacts
as requested in GitHub issue #27081, allowing users to see when artifacts were created.
Changes made:
- Add org.opencontainers.image.created annotation with Unix nanoseconds timestamp during artifact creation
- Preserve original creation timestamp when using --append option
- Update artifact inspect and add man pages to document the new functionality
- Add comprehensive e2e and system BATS tests to verify creation timestamp behavior
- Store timestamp as integer (Unix nanoseconds) for programmatic access
The creation timestamp helps users understand artifact freshness, particularly
useful for AI models and other time-sensitive artifacts managed by tools like RamaLama.
Usage examples:
podman artifact add myartifact:latest /path/to/file # Creates with timestamp
podman artifact inspect myartifact:latest # Shows created annotation as integer
podman artifact add --append myartifact:latest /file2 # Preserves original timestamp
Fixes: https://github.com/containers/podman/issues/27081
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
