feat: disable Next.js SIGTERM handler in Docker to allow custom shutdown-backup execution

feat: add NEXT_PUBLIC_CRISP_WEBSITE_ID secret mount to Docker build process

fix: deploy the production Shopify config, not the dev app

fix: shorten short_description to meet HF 60-char limit

docs: update Space references from solora-hq/Mixly to jay-hank/mixly

Initial commit: Mixly HF Space deploy config