Delivered: Comprehensive cross-platform E2E testing with 495+ tests across authentication, agents, canvas, workflows, stress testing, and automated bug discovery.

Key accomplishments:
- Test infrastructure foundation with API-first auth fixtures and Allure reporting
- 91 authentication and agent execution E2E tests
- 122 canvas and workflow E2E tests (7 canvas types, skills, DAG validation)
- 282+ stress, load, network, mobile, desktop, visual, and accessibility tests
- Automated bug discovery and filing with GitHub Issues integration
- Nightly/weekly stress test CI/CD workflows with alerting

See .planning/MILESTONES.md for full details.