[Persistence] Implement transactional repositories and atomic accepted-work recording #31

Outcome

Prevent partial state and ensure every accepted mutation has durable reconciliation work.

Scope

• Implement repositories for resources, status, plans, operations, decisions, audit, leases, and outbox with explicit transaction boundaries.

Acceptance criteria

• Resource mutation and outbox creation are atomic.
• Optimistic concurrency matches the public API.
• Rollback leaves no partial records and all queries enforce workspace scope.

Test and evidence

• Transaction, isolation, and fault-injection tests.

Dependencies

• Blocked by #30.
• Blocked by #21.

References

• Architecture overview
• Security model