feat: implement advanced reward management and wheel customization

- Add customizable background color
- Add wheel animations and sound effects
- Add reward description field and winner modal
- Change font to Dana
- Add configurable reward probabilities
- Support reward types (Empty, Discount Code, LiveCoin)
- Replace reward title with reward type selector
- Allow wheel page title customization from admin panel

backend/api/user.py

@@ -51,7 +51,10 @@ def spin(db: Session = Depends(get_db)):
         return {
             "winner": {
                 "id": winner.id,
-                "title": winner.title
+                "title": winner.title,
+                "prize": winner.prize,
+                "prize_type": winner.prize_type,
+                "description": winner.description or ""
             }
         }