update CI/CD workflows, fix YAML formatting, and enhance documentation with ADR references

CONTRIBUTING.md

@@ -11,6 +11,12 @@ Thank you for considering contributing to Linear Void!
 5. **Commit Messages**: Reference the relevant ADR (e.g., "feat(playout): add R2 sync per ADR-001").
 6. **Test with Docker**: Run `docker compose up --build` to test changes.
 
+## Repository
+
+- **Primary**: [git.allucanget.biz/zwitschi/linearvoid](https://git.allucanget.biz/zwitschi/linearvoid)
+- **Container Registry**: `git.allucanget.biz/zwitschi/linearvoid/<service>:latest`
+- **CI/CD**: Gitea Actions with self-hosted runners (see `.gitea/workflows/`)
+
 ## Code Style
 
 - Go: Use standard formatting (`go fmt`).
@@ -19,6 +25,7 @@ Thank you for considering contributing to Linear Void!
 
 ## Pull Requests
 
+- Open PRs on [Gitea](https://git.allucanget.biz/zwitschi/linearvoid).
 - Reference the related ADR in the PR description.
 - Ensure all tests pass and documentation is updated.
 - The CI workflow will validate normalization, linting, and Docker builds.