The original ci.yaml only triggered on push to main, meaning pushes to
feature branches (like argocd#8) never triggered CI.
Changes:
- Change push trigger from 'branches: [main]' to 'branches: ["**"]'
so pushes to any branch trigger CI
- Add workflow_dispatch for manual trigger capability
- Keep pull_request trigger for PR-based runs
- Preserve simple reusable workflow pattern
Fixes PRI-524: GitHub Actions CI not re-triggering on argocd#8 branch.
Co-Authored-By: Paperclip <noreply@paperclip.ing>