* fix: resolve GitHub Actions workflow validation errors in docker.yml - Fix usage of secrets context in conditional expressions - Add environment variables to build-docker and create-manifest jobs - Replace 'secrets.DOCKERHUB_USERNAME' with 'env.DOCKERHUB_USERNAME' in if conditions - Maintain secure handling of Docker Hub credentials through proper env context * Update .github/workflows/docker.yml Co-authored-by: Copilot <[email protected]> --------- Co-authored-by: Copilot <[email protected]>