Re-usable Complement GitHub CI workflow

[MadLittleMods]

As suggested by @anoadragon453,

Re-usable Complement GitHub CI workflow

Dev notes

• https://docs.github.com/en/actions/how-tos/reuse-automations/reuse-workflows

Pull Request Checklist

• Pull request is based on the develop branch
• Pull request includes a changelog file. The entry should:
  • Be a short description of your change which makes sense to users. "Fixed a bug that prevented receiving messages from other servers." instead of "Moved X method from EventStore to EventWorkerStore.".
  • Use markdown where necessary, mostly for code blocks.
  • End with either a period (.) or an exclamation mark (!).
  • Start with a capital letter.
  • Feel free to credit yourself, by adding a sentence "Contributed by @github_username." or "Contributed by [Your Name]." to the end of the entry.
• Code style is correct (run the linters)

[MadLittleMods]

I've tried out use_latest_deps and use_twisted_trunk in some CI runs and they appear to work. I don't know if the versions are actually being changed as expected.

• fa08b98 -> https://github.com/element-hq/synapse/actions/runs/22782133537
• f4e4152 -> https://github.com/element-hq/synapse/actions/runs/22841316669

[reivilibre]

• twisted_trunk: Updating twisted (25.5.0 -> 25.5.0.post0 508c44f) in the patch dependencies step, seems good

• latest_deps: less obvious to see but

  #23 [requirements 4/4] RUN --mount=type=cache,target=/root/.cache/uv if [ -z "1" ]; then uvx --with poetry-plugin-export==1.9.0 poetry@2.1.1 export --extras all -o /synapse/requirements.txt ; else touch /synapse/requirements.txt; fi

  #23 DONE 0.2s sounds like it

[reivilibre]

Have cut and diffed locally to be sure the move didn't lose anything and I'm satisfied

[MadLittleMods]

Thanks for the review @reivilibre 🦫