fix: replace index-based React keys with stable data keys (F-9)

Use page paths, referrer URLs, item names, and composite location
keys instead of array indices. Prevents stale-row glitches when
lists are filtered or reordered.

app/sites/[id]/funnels/page.tsx

@@ -117,7 +117,7 @@ export default function FunnelsPage() {
                       )}
                       <div className="flex items-center gap-2 mt-4">
                         {funnel.steps.map((step, i) => (
-                          <div key={i} className="flex items-center text-sm text-neutral-500">
+                          <div key={step.name} className="flex items-center text-sm text-neutral-500">
                             <span className="px-2 py-1 bg-neutral-100 dark:bg-neutral-800 rounded-lg text-neutral-700 dark:text-neutral-300">
                               {step.name}
                             </span>