feat(#74): Add token expiration for account deletion

supabase/migrations/20241112214000_add_token_cleanup_function.sql

@@ -0,0 +1,21 @@
+-- Enable the "pg_cron" extension
+create extension pg_cron with schema pg_catalog;
+
+grant usage on schema cron to postgres;
+grant all privileges on all tables in schema cron to postgres;
+
+-- Create a function to delete expired tokens
+CREATE OR REPLACE FUNCTION delete_expired_tokens()
+RETURNS void LANGUAGE plpgsql AS $$
+BEGIN
+  DELETE FROM account_deletion_requests
+  WHERE requested_at < NOW() - INTERVAL '24 hours';
+END;
+$$;
+
+-- Schedule the function to run every hour
+SELECT cron.schedule(
+  'delete_expired_tokens',
+  '0 * * * *',
+  'CALL delete_expired_tokens()'
+);