Ack — marks as reviewed. Disappears from Active, still visible in All. Use when activity is legitimate but worth noting.
Dismiss — hides as a false positive. Still queryable in All, just filtered out everywhere else.
Reopen — returns an acknowledged or dismissed alert to Active. Available in All view.
Bulk actions — tick one or more checkboxes; a bar appears above the table with Acknowledge / Dismiss / Reopen for the whole selection.
