fix(confidence-engine): v0.59c-layout — stack freshness beneath View report

Replace flex-row View report + status with flex-col stack so the
freshness label sits below the button and no longer floats between
actions on the Portfolio.

app/page.jsx

@@ -44,7 +44,7 @@ function Portfolio() {
 
             <div className="mt-4 flex gap-3 text-sm">
               {hasReport ? (
-                <div className="flex items-center gap-2">
+                <div className="flex flex-col gap-1 items-center">
                   <Link
                     href={`/investigations/${INVESTIGATION_ID}/report`}
                     className="rounded-lg border border-teal-600 bg-white px-4 py-2 font-medium text-teal-700 hover:bg-teal-50 transition"