Implement Integration Definition validator CLI with schema and index checks,
pytest suite, and CI workflow. Register open-cmis-tck and issue-core-gitea in
the integration index.
Closes OPEN-WP-0003 and OPEN-WP-0004.
OPEN-WP-0003: CLI validator for Integration Definition schema and index checks.
OPEN-WP-0004: Portfolio survey and registration of additional integrations.
