- Replaced Leaflet with OpenLayers for improved map rendering
- Added OpenLayers CSS and removed Leaflet CSS
- Updated map controller to use OpenLayers API
- Added marker icon in public directory
- Added scopes and associations for weather art in City model
This change migrates the map display from Leaflet to
OpenLayers, providing better performance and more features.
It also introduces new model associations for weather arts,
allowing to sort cities by latest weather updates.
