docs: Add QWEN.md file to customize Qwen Code interactions

Add a QWEN.md file to establish project context, preferences,
and behavior guidelines for Qwen Code interactions with the
aperonight Ruby on Rails project. This helps ensure consistent
and appropriate responses tailored to this specific project setup.

This change follows the convention of using a QWEN.md file to
customize AI assistant behavior in development environments.

test/fixtures/parties.yml

@@ -2,6 +2,7 @@
 
 one:
   name: Summer Party
+  slug: summer-party
   description: A great summer party with music and drinks
   state: published
   venue_name: Beach Club
@@ -12,10 +13,11 @@ one:
 
 two:
   name: Winter Gala
+  slug: winter-gala
   description: An elegant winter gala for the holidays
   state: draft
   venue_name: Grand Hotel
   venue_address: 456 Park Avenue
   latitude: 40.7589
   longitude: -73.9851
-  user: two
+  user: two