Fix DevContainer by switching from moby to docker

[tfaller]

If you currently try to open the repo in a DevContainer or a Github Codespace the creation of the container fails:

(!) The 'moby' option is not supported on Debian 'trixie' because 'moby-cli' and related system packages have been removed from that distribution.
(!) To continue, either set the feature option '"moby": false' or use a different base image (for example: 'debian:bookworm' or 'ubuntu-24.04').

This PR fixes this by disabling moby and using docker instead. Other potential fixes seemed not be fine to me:

• Using debian:bookworm: trixie is stable since August 2025. We should use the most recent stable Debian
• Using ubuntu-24.04: Would still be the recent release, however, not for long anymore. But the actual issue is, that the DevContainer feature ghcr.io/snebjorn/devcontainer-feature/chromium:latest does only seem to work on Debian. The creation with Ubuntu failed.

After disabling moby, the DevContainer worked for me as expected. Also docker-in-docker just worked. The script run-in-docker.sh can be run successfully. I’m not aware of what else relies on the docker-in-docker feature, as the commit (1ce95ff/#17095) that introduced it does not explain why it was added in the first place. It’s possible that something is broken due to the switch from moby to docker, but at least the container is functioning again instead of failing to start altogether.

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Summary by cubic

Fix DevContainer and Codespaces startup on Debian trixie by switching the docker-in-docker feature from Moby to Docker.

• Bug Fixes
  • Set "moby": false in .devcontainer/devcontainer.json so the container builds and docker-in-docker works (run-in-docker.sh succeeds).

^{Written for commit db9932f. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

[wing328]

thanks for the PR which has been merged