RG-25: First catalog adapter and synchronization

[hedhoud]

Context

The first adapter should target the organization's actual authoritative catalog and operating model.

Problem

Governance state, lineage, active configuration, and quality information can become inconsistent when synchronization is not idempotent, observable, or bounded by an agreed service level.

Expected behavior

• The selected catalog integrates with least-privilege access.
• Initial import, event updates, and scheduled reconciliation are idempotent.
• Approval and revocation changes propagate according to the declared authority.
• Synchronization lag is measured and limited.
• Outages follow the agreed policy.

Delivery dependency: RG-24 and access to the selected catalog.