Show when each extension was last updated

MCP, skill and tool rows in Settings say "Updated 5m ago" beside how
they're reached and who gets them. updated_at now means a change to an
extension's settings (an edit, or any Access save): runs, connections and
MCP syncs keep their own last_checked_at / last_synced_at and no longer
touch it.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/pages/admin/settings/(utils)/updated-ago.ts

@@ -0,0 +1,13 @@
+import checkedAgo from "./checked-ago";
+
+type Params = {
+    at: number | null;
+};
+
+/**
+ * When an extension's settings last changed, for a row's subtitle:
+ * "Updated 5m ago". Nothing when it's never been stamped.
+ */
+export default function updatedAgo({ at }: Params) {
+    return at ? `Updated ${checkedAgo({ at })}` : undefined;
+}