fixed frontend build

frontend/docker-entrypoint.prod.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+set -e
+
+# Real config (DATABASE_URL etc.) only exists as actual container env vars
+# at this point — injected via docker-compose.yaml's env_file — not during
+# the image build, so cache-warming has to happen here instead of a RUN
+# step in Dockerfile.prod.
+php bin/console cache:clear --env=prod --no-debug
+
+exec docker-php-entrypoint "$@"