refactor(cistech-tunnel): move runtime scripts to shared folder

- Add entrypoint.sh and startup-vnc.sh to shared folder
- Override command in docker-compose.json to use /shared/entrypoint.sh
- Scripts can now be modified without rebuilding image

apps/cistech-tunnel/shared/startup-vnc.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+set -e
+export HOME='/root'
+export USER='root'
+rm -f /tmp/.P1-lock /tmp/.X11-unix/X1 2>/dev/null || true
+rm -rf /tmp/.X*-lock /tmp/.X14-unix/* 2>/dev/null || true
+echo "Starting TigerVNC server on display :1..."
+vncserver :1 -geometry 1280x800 -depth 24 -SecurityTypes VncAuth -localhost no
+sleep 2
+echo "Starting noVNC on port ${NOVNC_PORT:-6092}..."
+websockify --web=/usr/share/novnc/ ${NOVNC_PORT:-6092} localhost:${VNC_PORT:-5901} &
+tail -f /root/.vnc/*.log