fix: support legacy systemd path parsing

install.sh

@@ -442,8 +442,8 @@ User=$ERP_USER
 Group=$ERP_GROUP
 Environment="ERP_INSTALL_ROOT=$INSTALL_ROOT"
 Environment="ERP_CONFIG_FILE=$CONFIG_FILE"
-WorkingDirectory="$INSTALL_ROOT"
-ExecStart="$INSTALL_ROOT/current/bin/erp-run"
+WorkingDirectory=$INSTALL_ROOT
+ExecStart=$INSTALL_ROOT/current/bin/erp-run
 Restart=always
 RestartSec=3
 TimeoutStopSec=90
@@ -453,12 +453,16 @@ NoNewPrivileges=true
 PrivateTmp=true
 ProtectSystem=full
 ProtectHome=true
-ReadWritePaths="$INSTALL_ROOT" "$CONFIG_ROOT" "$STATE_ROOT" "$LOG_ROOT"
+ReadWritePaths=$INSTALL_ROOT $CONFIG_ROOT $STATE_ROOT $LOG_ROOT
 
 [Install]
 WantedBy=multi-user.target
 EOF
     systemctl daemon-reload
+    if command -v systemd-analyze >/dev/null 2>&1; then
+      systemd-analyze verify /etc/systemd/system/kaidi-erp.service \
+        || fail 'generated systemd unit is invalid; run systemd-analyze verify /etc/systemd/system/kaidi-erp.service'
+    fi
     systemctl enable kaidi-erp.service
     systemctl restart kaidi-erp.service
   else