Change /insight/iteneraries

[3nd3r1]

Change endpoint and schemas to match endpoint in Commute-ai/commute-ai-agents.

1. Update the endpoint from insight/itinerary to /insight/iteneraries

2. Update the Request and Response schema
   ItineraryInsightRequest:

• itineraries: list[Itinerary]
• user_preferences: list[PreferenceBase]

ItineraryInsightResponse:

• itenerary_insights: list[ItineraryInsight]

ItineraryInsight:

• ai_insight: str
• leg_insights: list[LegInsight]

LegInsight:

• ai_insight: str

[zlendo1]

Closed with #50