[wolfy-j]

The DI manager used to send contract definition and binding events to the contract registry without waiting. A registry operation or transaction commit could therefore return before contract.get saw the change. Code that re-creates a contract entry and opens it right away failed with "contract definition '' not found".

Now each commit, or each single operation outside a transaction, goes to the contract registry as one contract.changes.apply batch:

• The registry checks every change in the batch, then applies them all under one lock and answers once with contract.accept or contract.reject. A refused batch changes nothing.
• The manager waits for that answer through the await service and updates its own state only after the batch is accepted.
• Each batch is sent and answered on its own path (di.changes/<seq>), so a late reply to an abandoned request cannot complete a newer one.
• AwaitService.Stop now releases pending waiters with an error, so a commit caught by shutdown does not hang until its timeout.

Known limit: if the reply never arrives (timeout or shutdown), the batch's outcome is unknown and the manager reports it as not applied.

Tests: a batch whose second change is refused leaves the registry unchanged. Commit sends one batch and returns only after the answer. A refused commit leaves manager state unchanged. A stale reply does not complete a newer operation. A waiter returns as soon as the await service stops. A definition re-created 200 times resolves right after every commit; before this change it failed on the first iteration.