GitLab 19.4 Adds Agentic Execution Governance

GitLab 19.4 adds delegated goals, MCP write-action approvals, inherited permissions, usage caps, and model-cost controls, extending the agentic CI/CD governance story introduced in 19.3. Bulk SAST remediation, scoped Secrets Manager capabilities, Flow Creator Agent, and Dedicated AI Gateway remain relevant, but independent implementation and governance evidence is limited.