Changelog

• f0cdf6f chore: bump version to v3.19.3 [skip-release] [skip ci]
• 4c9e52b feat(agent): add durable declared tasks
• d0ce554 feat(agent): verify declared task outcomes
• 19ef0d4 fix(serv): retry transient SQLite store locks
• 80db6cc fix(website): repair and rewrite the reactive-agent section