refactor: use Convex skip sentinel in query args

src/components/portal/portal-ticket-list.tsx

@@ -21,14 +21,14 @@ export function PortalTicketList() {
   const viewerId = (convexUserId ?? machineContext?.assignedUserId ?? null) as Id<"users"> | null
 
   const ticketsRaw = useQuery(
-    viewerId ? api.tickets.list : undefined,
+    api.tickets.list,
     viewerId
       ? {
           tenantId: session?.user.tenantId ?? DEFAULT_TENANT_ID,
           viewerId,
           limit: 100,
         }
-      : undefined
+      : "skip"
   )
 
   const tickets = useMemo(() => {