- Add SearchRoutes method to yandex client for on-demand station pair searches
- Implement hub expansion via on-demand /search calls in lazy graph expansion
- Integrate cache key generation for search results (search:{from}:{to}:{date})
- Update expandFromStation and expandFromCityHub to use Yandex API
- Add NewGraphWithoutYandex constructor for testability
- Add tests for on-demand search integration and cache TTL policies
This commit implements the core routing functionality for the trip planner MVP:
1. API handlers for city autocomplete, station listing, route search, and route GeoJSON
2. Router integration with Yandex Schedules API for building routing graphs
3. Pareto-optimal route search with max 1 transfer and MCT filtering
4. Cron job for station status detection and closure monitoring
5. Circuit breaker and rate limiter integration in Yandex client
6. Redis cache-aside layer for city directories and station lists
Co-Authored-By: Claude <noreply@anthropic.com>
