refactor: optimize includes for weather arts

- Changed includes for WeatherArt to optimize query
- Removed redundant includes of country in WeatherArt
- Simplified region fetching by directly ordering

These modifications improve the efficiency of the queries
by reducing unnecessary joins and utilizing ActiveRecord’s
query capabilities more effectively. The code change does not
affect the overall functionality but improves maintainability.

app/controllers/arts_controller.rb

@@ -3,7 +3,7 @@ class ArtsController < ApplicationController
     @regions = Region.all
     @current_region = Region.find(params[:region]) if params[:region].present?
 
-    @weather_arts = WeatherArt.includes(city: [ :country, { country: :region } ])
+    @weather_arts = WeatherArt.includes(city: [ :country ]).includes(:image_attachment)
 
     if @current_region
       @weather_arts = @weather_arts.joins(city: :country)

app/controllers/cities_controller.rb

@@ -3,7 +3,7 @@ class CitiesController < ApplicationController
   before_action :require_admin, only: [ :generate_weather_art ]
 
   def index
-    @regions = Region.includes(:countries).order(:name)
+    @regions = Region.order(:name)
     @cities = City.includes(:country, country: :region).order(:name)
 
     if params[:query].present?