fix: correct installation directory path in Proxmox LXC setup script

frontend/deploy/proxmox-lxc-setup.sh

@@ -5,12 +5,12 @@
 
 set -euo pipefail
 
-INSTALL_DIR="/opt/thermopro-frontend"
+INSTALL_DIR="/opt/frontend"
 DATA_DIR="/data"
 SERVICE_NAME="thermopro-frontend"
 
 if [[ $EUID -ne 0 ]]; then
-   echo "This script must be run as root (e.g. inside the LXC container)" >&2
+   echo "This script must be run as root inside the LXC container" >&2
    exit 1
 fi