✨ feat(shop): update shop management link in overview documentation

- change link reference from shop-myshop.md to shop-manage.md
- ensure accurate navigation for managing shops

Author: JoField08

Writerside/topics/shop-overview.topic

@@ -20,7 +20,7 @@
                 Shop erstellen
             </card>
 
-            <card href="shop-myshop.md" badge="settings"
+            <card href="shop-manage.md" badge="settings"
                   summary="Verwalte deine Shops, ändere Preise und kontrolliere dein Lager.">
                 Shop verwalten
             </card>