Automatically build and promote overcloud host images

[MoteHue]

When updates to pulp-repo-versions.yml are pushed, new overcloud host images are automatically built.
Once the images build successfully, a new PR is proposed to SKC to bump the host image tags.
If this fails, we're now alerted in #release-train-alerts
The auto-promotion workflow is extended to automatically promote host images too.

[MoteHue]

Here's examples of the trigger:

1. when pulp-repo-versions is not changed: https://github.com/stackhpc/stackhpc-kayobe-config/actions/runs/17800119094
2. When pulp-repo-versions is changed: https://github.com/stackhpc/stackhpc-kayobe-config/actions/runs/17799778857

[MoteHue]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces automation for building and promoting overcloud host images, triggered by changes to pulp-repo-versions.yml. The changes include adding a new path filter configuration for GitHub Actions and a release note for this new feature. My review focuses on improving the clarity of a configuration comment and enhancing the readability of the release note. The changes are straightforward and well-aligned with the PR's goal.

[MoteHue]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces automation to build overcloud host images when pulp-repo-versions.yml is updated. The changes are well-structured, adding a new path filter for GitHub Actions and a corresponding release note. The renaming of .github/path-filters.yml to a more specific name is also a good improvement for clarity. I have one minor suggestion for the release note to improve its readability for a wider audience.

[MoteHue]

This is good for review again @Alex-Welsh @seunghun1ee :)

[Alex-Welsh]

recheck failed to reach upper constraints