refactor(ui): redesign playlist detail header

- Move back button to cover image area with updated styling
- Remove sticky top bar for cleaner view
- Add explicit container names in docker-compose.yml

docker-compose.yml

@@ -2,12 +2,14 @@ version: '3.8'
 
 services:
   music-canvas:
+    container_name: music-canvas
     build: .
     ports:
       - "7481:3000"
     restart: unless-stopped
 
   sync-service:
+    container_name: music-sync-server
     build: ./sync-server
     ports:
       - "7482:3001"