[Persistence] Design relational state, migrations, tenant constraints, and outbox #30

Outcome

Represent desired, observed, operation, policy, audit, lease, and enqueue state with enforceable invariants.

Scope

• Model resources, generations, observations, operations, immutable plans, decisions, audit, leases, and an outbox with encryption and migration rules.

Acceptance criteria

• Stable identity, parent, workspace, generation, and atomicity constraints are enforced.
• Secrets are excluded and backup scope is explicit.
• Fresh-install, upgrade, failed-migration, and rollback-boundary tests exist.

Test and evidence

• Schema review, migration test matrix, and backup inventory.

Dependencies

• Blocked by #29.
• Blocked by #20.
• Blocked by #26.
• Blocked by #27.
• Blocked by #12.

References

• Architecture overview
• Security model