feat: improve DALL-E prompt generation for weather scenes

- Update the prompt to specify generating a highly detailed and
  photorealistic image for a specific weather moment.
- Enhance clarity regarding the scene's inspiration by retaining
  context about the city, state, country, and region.

This change refines the AI generation process by focusing on
particular weather moments, improving the output's relevance and
detail, which could lead to a better user experience.

app/services/ai_service.rb

@@ -71,8 +71,7 @@ class AiService
     state = city.state&.name || ""
 
     <<~PROMPT
-      Ultra-realistic photography of #{city.name}, #{state}, #{country}, #{region}.
-      captured with Phase One IQ4 150MP medium format camera, Hasselblad XCD 45mm f/4 lens.
+      Generate a highly detailed and photorealistic DALL-E 3 prompt capturing a specific weather moment in #{city.name}, #{state}, #{country}, #{region}.
 
       **Scene Inspiration:**
       #{city_desc}