chore: checkpoint before block builder refactor

.env.example

@@ -4,6 +4,9 @@ APP_KEY=
 APP_DEBUG=true
 APP_URL=http://localhost
 
+# Optional: max requests/minute per IP for public /r/{slug} and subscribe (default: 1000 when APP_ENV is local|testing, else 60).
+# PUBLIC_REQUESTS_PER_MINUTE=120
+
 # Wall-clock times from the admin UI (datetime-local) are interpreted in this zone.
 APP_TIMEZONE=Europe/Amsterdam