refactor: render nginx templates into configuration directory

nginx/compose.yaml

@@ -5,10 +5,10 @@ services:
     container_name: nginx
     volumes:
       - /srv/data/nginx/templates:/etc/nginx/templates:ro
-      - /srv/data/nginx/snippets:/etc/nginx/snippets:ro
       - /srv/data/nginx/certs:/etc/nginx/certs:ro
     environment:
       BASE_DOMAIN: ${BASE_DOMAIN}
+      NGINX_ENVSUBST_OUTPUT_DIR: /etc/nginx
     ports:
       - "192.168.10.101:80:80"
       - "192.168.10.101:443:443"