test(api): cover search visibility-filter narrowing; note pagination cap rationale

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

crates/api/src/admin_search.rs

@@ -79,6 +79,8 @@ pub(crate) async fn search_objects(
         }));
     }
 
+    // Search uses a tighter default/cap (20, max 50) than the shared `Pagination`
+    // (default 50, max 200): result pages are slower to scan than a raw object list.
     let offset = params.offset.unwrap_or(0).max(0) as usize;
     let limit = params.limit.unwrap_or(20).clamp(1, 50) as usize;