Enable Moby on Ubuntu 26.04 (Resolute)

`docker-in-docker` currently rejects Ubuntu 26.04 (`resolute`) when `moby: true`:

```text
The 'moby' option is not supported on ubuntu 'resolute' because 'moby-cli' and related system packages are not available in that distribution.
```

However, Microsoft now publishes Moby packages for Ubuntu 26.04, including `moby-cli`, `moby-engine`, `moby-containerd`, and `moby-buildx`.

> This is similar to the already closed #1633 / #1640 / #1660 , **but the upstream situation has changed since then, so I’d like to ask whether this can be reconsidered.**

The current script still excludes `resolute` from:

```bash
DOCKER_MOBY_ARCHIVE_VERSION_CODENAMES
```

and explicitly blocks `resolute` when `USE_MOBY=true`.

Would it be possible to enable Moby support for Resolute and add a corresponding test?

Related: #1633, #1640, #1660

Start in the docker-in-docker script by locating DOCKER_MOBY_ARCHIVE_VERSION_CODENAMES and the USE_MOBY=true validation that rejects resolute. Review the related tests and add coverage for Ubuntu 26.04 with Moby enabled; it is done when the test passes and Resolute is no longer rejected.

Written by the indexing model from the issue text.