Add more information to version command (I want to see the image)

[christianh814]

What would you like to be added:

There's currently no way to know what the default image is based on the version alone

$ kind  version 
kind v0.31.0 go1.25.5 linux/amd64

I would be nice to "bulk up" the version command to output more information with either -o yaml or -o json

Example:

$ kind version -o json
{
  "kind": {
    "version": "v0.31.0",
    "gitCommit": "somelongstring",
    "platform": "linux/amd64",
    "defaultImage": "kindest/node:v1.35.0@sha256:452d707d4862f52530247495d180205e029056831160e22870e37e3f6c1ac31f"
  }
}

This will also provide a way to add information in the future.

This puts it in par with kubectl version -o json

Why is this needed:

Instead of creating sub-commands for superfluous information, it would be good to have it in one location and version seems like the obvious choice.

[BenTheElder]

There's currently no way to know what the default image is based on the version alone

No purely automated way from the command line that does not involve creating a cluster (docker inspect kind-control-plane), but we do publish this in every release note and users definitely parse the available images there 🙈 (see other issues discussing that)

What's the use case for reading just the default node image, and these other fields?

We avoid adding features without a really strong use-case and no other way to accomplish them, because kind is already tricky to maintain and must support Kubernetes @ HEAD so we depend on being lightweight and focused. As-is we need help with some involved upkeep e.g. #3795

Exposing the commit info would also change that go install is ~identical from tagged releases versus make install.