add supabase stack

from https://github.com/supabase/supabase/docker

stack/supabase/volumes/functions/hello/index.ts

@@ -0,0 +1,16 @@
+// Follow this setup guide to integrate the Deno language server with your editor:
+// https://deno.land/manual/getting_started/setup_your_environment
+// This enables autocomplete, go to definition, etc.
+
+import { serve } from "https://deno.land/std@0.177.1/http/server.ts"
+
+serve(async () => {
+  return new Response(
+    `"Hello from Edge Functions!"`,
+    { headers: { "Content-Type": "application/json" } },
+  )
+})
+
+// To invoke:
+// curl 'http://localhost:<KONG_HTTP_PORT>/functions/v1/hello' \
+//   --header 'Authorization: Bearer <anon/service_role API key>'