disable clans navigation, fix navbar extension bug on new tab

src/elm/components/NavigationBar.py

@@ -37,7 +37,8 @@ class NavigationButton(Component):
         else:
             self.session.navigate_to(self.target_url)
 
-        await self.extension_state_changed(None)
+        if self.extension_state_changed is not None:
+            await self.extension_state_changed(None)
 
 
     def is_active(self) -> bool:

src/elm/components/UserNavigation.py

@@ -93,7 +93,7 @@ class UserNavigation(Component):
                 UserNavigationButton(f"Guthaben: {self.session[AccountingService].make_euro_string_from_decimal(self.balance)}", "/balance", self.close_navigation),
                 UserNavigationButton("Meine Bestellungen", "/my-orders", self.close_navigation),
                 UserNavigationButton("Mein Profil", "/my-profile", self.close_navigation),
-                UserNavigationButton("Mein Clan", "/my-clans", self.close_navigation),
+                # UserNavigationButton("Mein Clan", "/my-clans", self.close_navigation),  ToDo: Implement
                 UserNavigationButton("Ausloggen", "/logout", self.close_navigation)
             ),
             min_width=3.5,