feat: enforce admin role checks in layouts and navbar navigation

shop/components/Navbar.tsx

@@ -38,12 +38,23 @@ export async function Navbar() {
   );
 
   let user = null;
+  let role = "partner";
   try {
     const { data } = await supabase.auth.getUser();
     user = data.user;
+    if (user) {
+      const { data: dbUser } = await supabase
+        .from("users")
+        .select("role")
+        .eq("id", user.id)
+        .single();
+      if (dbUser) {
+        role = dbUser.role;
+      }
+    }
   } catch (error) {
     console.error("Fehler beim Abrufen des Users in Navbar:", error);
   }
 
-  return <NavbarClient user={user} />;
+  return <NavbarClient user={user} role={role} />;
 }