chromiumoxide's fetcher has no linux/arm64 build, so on the Pi the crawler's browser launch failed with 'OS linux aarch64 is not supported'. Build the backend image with INSTALL_CHROMIUM=true (Debian chromium-headless-shell, verified present + runnable on trixie/arm64 at /usr/bin/chromium-headless-shell) and set CRAWLER_CHROMIUM_BINARY to it in .env so the launcher uses the system binary instead of the fetcher. Backend image only; frontend unchanged. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>