fix(zammad): configure Elasticsearch for LXC container startup

- Set discovery.type: single-node (required for single-node ES)
- Set xpack.security.enabled: false (not needed in local LXC)
- Set bootstrap.memory_lock: false (fails in unprivileged LXC)
- Add startup wait loop (up to 60s) to ensure ES is ready before
  Zammad installation continues

Fixes #12301-related recurring Elasticsearch startup failures

install/zammad-install.sh

@@ -30,10 +30,21 @@ setup_deb822_repo \
 $STD apt install -y elasticsearch
 sed -i 's/^-Xms.*/-Xms2g/' /etc/elasticsearch/jvm.options
 sed -i 's/^-Xmx.*/-Xmx2g/' /etc/elasticsearch/jvm.options
+cat <<EOF >>/etc/elasticsearch/elasticsearch.yml
+discovery.type: single-node
+xpack.security.enabled: false
+bootstrap.memory_lock: false
+EOF
 $STD /usr/share/elasticsearch/bin/elasticsearch-plugin install ingest-attachment -b
 systemctl daemon-reload
 systemctl enable -q elasticsearch
 systemctl restart -q elasticsearch
+for i in $(seq 1 30); do
+  if curl -s http://localhost:9200 >/dev/null 2>&1; then
+    break
+  fi
+  sleep 2
+done
 msg_ok "Setup Elasticsearch"
 
 msg_info "Installing Zammad"