fix: prevent crash when selecting nodes

We got a Error: Objects are not valid as a React child when selecting any node, due to the recently re-enabled SelectionConfig not dealing with all possible attribute types. A fairly stop-gap solution but it does the trick :)

libs/shared/lib/vis/components/config/SelectionConfig.tsx

@@ -38,7 +38,7 @@ export const SelectionConfig = () => {
             if (key === 'labels' || key === '_id') return null;
             return (
               <div key={index + key} className="flex justify-between items-center px-4 py-1 gap-1">
-                <span className="text-xs font-normal break-all max-w-[6rem]">{key}</span>
+                <span className="text-xs font-normal break-all max-w-[6rem]">{String(key)}</span>
                 <span className="text-xs break-all">{value as string}</span>
               </div>
             );