refactor: formalize safety rules, extract shared styles, reconcile docs (P2)
- Add backend/app/safety.py with explicit confirmation policy, multi-intent
semantics, and MCP error taxonomy with retry classification
- Add 26 unit tests for safety module (confirmation rules, error taxonomy)
- Extract repeated inline styles into shared CSS classes in index.css
(section-card, stat-label, status-badge, data-table, empty/error-state,
pagination-bar)
- Refactor DashboardPage, ReplayListPage, ReplayPage to use shared classes
- Update README: add missing API endpoints, document safety/confirmation rules
- Use proper HTML entities for arrow/dash characters to fix encoding glitches
036e12349d