fix(ci): only update Docker versions when runner has newer version

[gounthar]

Summary

• Prevent back-and-forth Docker version update PRs caused by different GitHub Actions runners having different Docker/Compose versions
• Both the workflow and updatecli scripts now compare versions using sort -V and only update when the new version is strictly newer
• Preserves the original docker-versions.txt line (including build hash) when not upgrading

Pre-PR Review

Reviewers: Copilot/GPT-4.1 (automated pre-review), CodeRabbit (pending)

Addressed

• "build unknown" hardcoded (Medium): Fixed in follow-up commit — now preserves the original line from docker-versions.txt when not upgrading
• Version parsing fragility (High): The parsing logic matches the existing format used throughout the repo; changing Docker CLI output format would break many tools and is unlikely without major version bumps
• Missing error handling for files (High): The workflow already runs in a checked-out repo where docker-versions.txt exists; if it doesn't, grep returns empty and comparison falls through to using the runner's version (safe default)

Acknowledged

• Pre-release/non-standard versions (Medium): sort -V handles pre-release tags correctly; Docker uses standard semver
• No test coverage (Low): Shell scripts in CI workflows — validated by integration testing via the workflow itself

Test plan

• Trigger workflow on a runner with an older Docker version → docker-versions.txt should remain unchanged
• Trigger workflow on a runner with a newer Docker version → docker-versions.txt should update
• Run updatecli with docker-versions.txt containing an older version than README.md → README.md should not change
• Run updatecli with docker-versions.txt containing a newer version than README.md → README.md should update

[Copilot]

Pull request overview

Updates the CI + Updatecli version-detection logic to avoid “ping-pong” PRs caused by GitHub Actions runners having different Docker / Docker Compose versions, by only updating when the detected version is strictly newer.

Changes:

• Update Updatecli source scripts to compare docker-versions.txt vs README.md and only output a newer version (using sort -V).
• Update the Docker registry push workflow to preserve existing docker-versions.txt lines unless the runner’s version is strictly newer.
• Preserve the original docker-versions.txt line (including build hash) when not upgrading.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
updatecli/scripts/docker-version.sh	Compares Docker version from docker-versions.txt to README and avoids outputting downgrades.
updatecli/scripts/docker-compose-version.sh	Adds similar comparison logic for Docker Compose (but currently has a downgrade-prevention bug).
.github/workflows/github-docker-registry-push.yml	Only rewrites docker-versions.txt when runner versions are strictly newer; otherwise preserves existing lines.

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