2.5.19

Embedded SQLite reliability

This patch prevents concurrent SQLite writes from failing V2 workflow and activity task claims, or activity result publication.

• Acquire SQLite's writer before reading claim and publication state.
• Keep activity execution outside result publication, so publishing an existing result does not repeat the callback.
• Preserve original task identities, attempt limits and deadlines, with the existing bounded rollback safeguards.

There are no schema changes. Update the package and gracefully restart long-lived workers to load the correction.

composer require durable-workflow/workflow:^2.5.19

Details: #783