cistech-tunnel: move all scripts to dynamic mounts

- Move entrypoint.sh from build/scripts/ to shared/ (no longer baked into image)
- Add entrypoint directive to docker-compose.json pointing to /shared/entrypoint.sh
- Update entrypoint.sh to reference /shared/startup-vnc.sh instead of /opt/scripts/
- Bump tipi_version to 7

All scripts are now dynamically controlled via volume mounts from the shared/
directory. The Docker image is a clean base with only packages installed.

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

apps/cistech-tunnel/config.json

@@ -6,7 +6,7 @@
   "dynamic_config": true,
   "id": "cistech-tunnel",
   "description": "openconnect-sso in Docker with noVNC web UI for accessing cistech environments. Native Docker - no VM overhead.",
-  "tipi_version": 6,
+  "tipi_version": 7,
   "version": "5.1.14.145",
   "categories": [
     "utilities"