Fix SQLite contention in embedded V2 workflow starts, signals and task handling.
Use the configured Workflow storage database when it differs from the application database.
Safe mutation retries require proof that the original root transaction rolled back. Workflow execution acquires SQLite's write lock before reading durable state or entering application code. Activity result recording retries independently of the activity callback, preserving original attempts and deadlines. Nested transactions and uncertain commit or rollback acknowledgements keep their original errors.
The correction supports the existing Laravel 9–13 range. Other database transaction behavior remains unchanged.