Integrate AI-Agents Service Client

[3nd3r1]

• HTTP client configured to communicate with ai-agents service
• Integrate /route/search endpoint with ai-agents service
  • Update itinerary schema with optional (nullable) ai_description which we acquire using api/v1/insight/itinerary in get_itinerary_insight
  • Remove ai_description from RouteSearchResponse
  • Refactor get_route_insight to use proper nomenclature of get_leg_insight and api/v1/insight/leg route
• Service client handles connection errors gracefully
• Handles failures gracefully

[zlendo1]

Closed with #30

[zlendo1]

Wrongfully closed, reconfigured structure

[zlendo1]

Closed with #41