Backend:
- /api/validation/ CRUD for validation tasks (policies)
- Run history with 6 filters + pagination
- Alembic migrations (provider_id, policy_id)
- 28 pytest tests
Frontend:
- /validation — task list page with status filters + CRUD
- /validation/[id] — task config (Config + History tabs)
- /validation/history — run history with metrics
- Sidebar nav entry under Operations
- i18n en/ru
Playwright (ScreenshotService):
- Removed 25s hardcoded sleeps → conditional waits
- CDP fallback to full_page screenshot
- Total timeout enforcement (120s)
- Debug screenshots → temp dir with cleanup
QA fixes:
- Debug screenshot accumulation in production (tempdir + rmtree)
- Frontend API payload field name mismatch
- History issues field reference fix
- delete_runs scoped by policy_id
Belief protocol:
- @RATIONALE/@REJECTED on 27 C4+ contracts
Closes: VALIDATION-REWORK-2026