Adds .github/workflows/review.yml to run AI code review on PRs using
SAP AI Core. Three reviewers: sonnet, gpt, security (same as Gitea CI).
Uses the .gitea/actions/review composite action which auto-detects
GitHub vs Gitea runners via GITHUB_API_URL and uses GitHub REST API
accordingly. action-repo points to strat/review-bot for binary downloads.
Required secrets: SONNET_REVIEW_TOKEN, GPT_REVIEW_TOKEN, AICORE_*
Rodin