Transactional domain events in the core #360

Area: database transactions, application lifecycle, first-party packages

Problem

Applications need to react to committed model or domain changes, but emitting events inside a transaction can publish work that later rolls back.

Proposal

Introduce a minimal event dispatcher with afterCommit delivery, nested transaction handling, listener priorities, and synchronous execution. Queue integration remains an adapter owned by the queue package.

Acceptance criteria

• Events registered inside a committed transaction run once after the outer transaction commits.
• Rollbacks discard pending events.
• Nested transactions and multiple database connections are tested.
• Listener failures have documented propagation and logging behavior.