feat(ui): hint Enter-to-commit in default table search placeholder

The default DataTableSearch placeholder now reads "Search... (press Enter)"
so the commit-on-Enter behavior is discoverable across every table that does
not pass a custom placeholder.

ui/components/shadcn/table/data-table-search.tsx

@@ -44,7 +44,7 @@ export const DataTableSearch = ({
   controlledValue,
   onSearchChange,
   onSearchCommit,
-  placeholder = "Search...",
+  placeholder = "Search... (press Enter)",
   badge,
 }: DataTableSearchProps) => {
   const searchParams = useSearchParams();