fix: add missing trait stubs to test mock impls

crates/presentation/tests/api_test.rs

@@ -85,6 +85,7 @@ impl UserRepository for NobodyUserRepo {
     async fn find_by_email(&self, _: &Email) -> Result<Option<User>, DomainError> { Ok(None) }
     async fn save(&self, _: &User) -> Result<(), DomainError> { panic!() }
     async fn find_by_id(&self, _: &UserId) -> Result<Option<User>, DomainError> { panic!() }
+    async fn list_with_stats(&self) -> Result<Vec<domain::models::UserSummary>, DomainError> { panic!() }
 }
 
 async fn test_app() -> Router {