feat: Implement Yandex integration and city infrastructure components

- Add Yandex API Connector (core/yandex_connector.py): Complete integration with Yandex.Maps, Yandex.Transport, Geocoder, and SpeechKit APIs for online operation with authentication, rate limiting, and caching
- Add Yandex Offline Cache (core/yandex_cache.py): Comprehensive offline caching system for Yandex Maps data with SQLite storage, compression, and intelligent prefetching
- Add City Mesh Bridge (mesh/city_mesh_bridge.py): Gateway between mesh networks and city IoT devices supporting MQTT, CoAP, LoRaWAN protocols with emergency broadcast capabilities
- Add Userver Bridge (core/userver_bridge.cpp): C++ userver service module with FFI interface for Flutter communication, HTTP REST API, WebSocket support, and data processing
- Add GeoAI Routing (ai/geoai_routing.py): AI-powered route prediction using machine learning models, real-time traffic integration, and mesh network topology awareness

These components enable:
- Seamless Yandex service integration with offline fallback
- Decentralized city infrastructure communication
- High-performance Flutter-native backend services
- Intelligent routing with AI predictions and mesh optimization
- Cross-platform urban connectivity and navigation

Author: sorydima