fix(db): skip UPDATE and audit on no-op object update (keep updated_at consistent)

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

crates/db/src/catalog.rs

@@ -188,6 +188,12 @@ pub async fn update_object(
         return Ok(false);
     };
 
+    let changes = update_changes(&old.to_input(), input);
+    if changes.is_empty() {
+        // No-op: don't touch updated_at or the audit log.
+        return Ok(true);
+    }
+
     sqlx::query(
         "UPDATE object SET \
          object_number = $2, object_name = $3, number_of_objects = $4, \
@@ -208,9 +214,6 @@ pub async fn update_object(
     .execute(&mut *conn)
     .await?;
 
-    let changes = update_changes(&old.to_input(), input);
-
-    if !changes.is_empty() {
     audit::record(
         &mut *conn,
         &NewAuditEvent {
@@ -222,7 +225,6 @@ pub async fn update_object(
         },
     )
     .await?;
-    }
 
     Ok(true)
 }