mobile: fix last heading not shown in toc

apps/mobile/app/components/sheets/toc/index.tsx

@@ -129,6 +129,7 @@ const TableOfContents = ({ toc, close }: TableOfContentsProps) => {
           <TableOfContentsItem item={item} close={close} />
         )}
         keyExtractor={(item) => item.id}
+        ListFooterComponent={<View style={{ height: 50 }} />}
       />
     </View>
   );