feat: travel service with 2GIS routing, POI, hotels + finance providers + UI overhaul

- Add travel-svc microservice (Amadeus, TravelPayouts, 2GIS, OpenRouteService)
- Add travel orchestrator with parallel collectors (events, POI, hotels, flights)
- Add 2GIS road routing with transport cost calculation (car/bus/taxi)
- Add TravelMap (2GIS MapGL) and TravelWidgets components
- Add useTravelChat hook for streaming travel agent responses
- Add finance heatmap providers refactor
- Add SearXNG settings, API proxy routes, Docker compose updates
- Update Dockerfiles, config, types, and all UI pages for consistency

Made-with: Cursor

backend/internal/types/widgets.go

@@ -12,6 +12,17 @@ const (
 	WidgetImageGallery WidgetType = "image_gallery"
 	WidgetVideoEmbed   WidgetType = "video_embed"
 	WidgetKnowledge    WidgetType = "knowledge_card"
+
+	WidgetTravelMap        WidgetType = "travel_map"
+	WidgetTravelEvents     WidgetType = "travel_events"
+	WidgetTravelPOI        WidgetType = "travel_poi"
+	WidgetTravelHotels     WidgetType = "travel_hotels"
+	WidgetTravelTransport  WidgetType = "travel_transport"
+	WidgetTravelItinerary  WidgetType = "travel_itinerary"
+	WidgetTravelBudget     WidgetType = "travel_budget"
+	WidgetTravelClarifying WidgetType = "travel_clarifying"
+	WidgetTravelActions    WidgetType = "travel_actions"
+	WidgetTravelContext    WidgetType = "travel_context"
 )
 
 type ProductData struct {