Restructure cistech-tunnel to match rego-tunnel pattern

- build/: Dockerfile + entrypoint.sh (base image with VNC/noVNC)
- shared/: Runtime scripts mounted into container
  - xstartup: VNC startup, launches openconnect-vpn in xterm
  - openconnect-vpn: Main VPN script with menu, auto-connect, watchdog
- Removed source/ folder (replaced by build/)
- Updated docker-compose.json with proper volume mounts
- Changed port to 6080 (noVNC default)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/cistech-tunnel/shared/xstartup

@@ -0,0 +1,39 @@
+#!/bin/bash
+# VNC xstartup - launches terminal with openconnect-vpn script
+
+unset SESSION_MANAGER
+unset DBUS_SESSION_BUS_ADDRESS
+
+# Import environment variables from container (PID 1)
+# VNC doesn't inherit Docker env vars, so we source them here
+while IFS= read -r -d '' line; do
+    export "$line"
+done < /proc/1/environ
+
+export XDG_RUNTIME_DIR=/tmp/runtime-root
+mkdir -p $XDG_RUNTIME_DIR
+chmod 700 $XDG_RUNTIME_DIR
+
+# GPU/WebKit workarounds
+export GDK_BACKEND=x11
+export WEBKIT_DISABLE_DMABUF_RENDERER=1
+
+# Start dbus session
+[ -x /usr/bin/dbus-launch ] && eval $(dbus-launch --sh-syntax --exit-with-session)
+
+# Start window manager
+openbox &
+sleep 2
+
+# Disable screen blanking and power saving
+xset s off 2>/dev/null || true
+xset -dpms 2>/dev/null || true
+xset s noblank 2>/dev/null || true
+
+# Make script executable and launch in terminal
+chmod +x /shared/openconnect-vpn 2>/dev/null || true
+xterm -fa 'Monospace' -fs 11 -bg black -fg white -geometry 130x45+10+10 \
+    -title "Cistech VPN Terminal" \
+    -e "bash -c '/shared/openconnect-vpn; exec bash'" &
+
+wait