update secrets

.env.example

@@ -36,3 +36,10 @@ RATE_LIMIT_WINDOW=60
 # Waitlist (set to true to enable waitlist gate on /auth/signup)
 WAITLIST_MODE=false
 RESEND_AUDIENCE_WAITLIST=
+
+# R2 Backup (optional — enables materia-backup.timer when all three are set)
+# Get from: Cloudflare Dashboard → R2 → Manage R2 API Tokens
+# R2_ENDPOINT format: https://<account_id>.r2.cloudflarestorage.com
+R2_ACCESS_KEY_ID=
+R2_SECRET_ACCESS_KEY=
+R2_ENDPOINT=