- Created src/17-testing/ chapter with complete testing documentation
- Added README.md - testing overview and structure
- Added e2e-testing.md - comprehensive E2E testing guide (447 lines)
- Added architecture.md - testing architecture and patterns (410 lines)
- Updated SUMMARY.md to include Part XIV - Testing
- All E2E testing documentation now centralized in botbook
- Developers refer to botbook and test PROMPT.md, not scattered files
