docs: link to sql-rest translator in js reference (supabase#30656)

Author: charislam

apps/docs/docs/ref/javascript/introduction.mdx

@@ -5,3 +5,5 @@ hideTitle: true
 ---
 
 This reference documents every object and method available in Supabase's isomorphic JavaScript library, `supabase-js`. You can use `supabase-js` to interact with your Postgres database, listen to database changes, invoke Deno Edge Functions, build login and user management functionality, and manage large files.
+
+To convert SQL queries to `supabase-js` calls, use the [SQL to REST API translator](/docs/guides/api/sql-to-rest).