[Suggestion] Metadata and json output in distrobox v2

**Is your feature request related to a problem? Please describe.**
Hello, I'm the developer of DistroShelf, a gtk4 GUI for distrobox. I've just seen you guys are planning on doing a v2 rewrite. Could you add some metadata in the v2 version, so that external programs can more easily interface with distrobox?

**Describe the solution you'd like**
Podman (and I guess docker as well) supports the `--format json` argument for most commands. That provides the output as json. An external program such as DistroShelf could use that to interface with distrobox.

Also, a "v2" version metadata in the exported .desktop files would be helpful, so that external programs can list the exported files from distrobox v1, see that the version is different, and prompt the user to upgrade the old .desktop exports.

**Additional context**
distrobox is great! Thanks for building it. Being able to run programs from any distro is kind of magic