Public surface: repository descriptions, topics and README CI badges #589

Make the first screen of each dmfdeploy repository say what the repository is.

Scope:

• Descriptions and topics. Set on all ten repositories with gh repo edit on 2026-10-05. Each description restates that repository's README in one line.
• CI badge. One PR per repository that runs ci.yml, adding a status badge at the top of the README:
  • docs: add CI badge to README #588
  • docs: add CI badge to README dmf-cms#157
  • docs: add CI badge to README dmf-infra#90
  • docs: add CI badge to README dmf-env#23
  • docs: add CI badge to README dmf-init#40
  • docs: add CI badge to README dmf-media#36
  • docs: add CI badge to README dmf-runbooks#48
  • docs: add CI badge to README dmf-promsd#9
  • docs: add CI badge to README dmf-central#8
• Pinned repositories. Set by hand in the organization settings. No API exists for this.

The .github repository has no root README, so it gets no badge.

Done when every badge PR has merged. The PRs reference this issue without closing it, so close it by hand after the last one lands.

This issue replaces the per-repository tracking issues opened the same day. Those were closed because cross-repo batches take one umbrella issue that every per-repo PR references (docs/WORKING-MODEL.md).