File locations + service commands

Path	What lives there
`/opt/bng-deploy/`	The webui shim (Flask app, venv, static assets, /bin/ scripts)
`/opt/bng-deploy/data/`	User store, API keys, session store, settings, sqlite audit log
`/opt/bng-deploy/data/.controller_key`	The shim's own key for talking to the controller. Not for operator use.
`/opt/bng-deploy/data/.bootstrap_token`	The first-run setup wizard token (consumed on first use)
`/var/lib/quantum-controller/`	Controller state: `controller.db` (SQLite), `api_keys.json`, `audit.log`, `bng.json`
`/opt/quantumtouch/data/prometheus/`	Prometheus TSDB (14-day retention default)
`/opt/quantumtouch/etc/scrape-token`	The Prometheus scrape token
`/opt/bng-demo/`	CPESIM plugin install root (only if installed via Toybox)
`/etc/vpp/startup.conf`	VPP dataplane config — `cpu {}` block controls worker pinning
`/etc/systemd/system/bng-deploy.service.d/10-timeout.conf`	Gunicorn `--timeout` override installed by the wrapper

Service commands:

sudo systemctl status vpp vpp-bridge quantum-controller bng-deploy quantumtouch-prometheus
sudo systemctl restart bng-deploy               # webui restart, no dataplane impact
sudo journalctl -u quantum-controller -f        # tail controller log
sudo journalctl -u bng-deploy -f                # tail webui log
sudo vppctl show interface                      # VPP interface state
sudo vppctl show errors                         # VPP node error counters
sudo vppctl show threads                        # VPP worker mapping