updated: tutorial with geospatial hotel search implementation

- Refactor GraphQL schema to use nested Airport type with location
- Update resolver with SQL++ CTE for geospatial distance calculations
- Implement dual-layer map visualization (hotels + airports)
- Add differentiated tooltips (full details for hotels, name only for airports)
- Simplify frontend code and remove complex zoom calculations
- Update tutorial documentation with comprehensive geospatial examples
- update the screenshots for the new use case

Author: VirajAgarwal1