feat(cloud): single-shot deploy.sh + FROST stack + healthchecks

Stage 5 — make the cloud composition spin up in one command and add
the SensorThings (FROST) stack as a fully segregated tenant.

cloud/deploy.sh — idempotent, 7-step bring-up:
  preflight → validate → up + wait → cert state → issue/renew →
  service status → endpoint smoke test. Reissues LE cert only when
  current issuer no longer matches ACME_CA_URI. Move-aside-then-
  restore-on-failure so the bootstrap cert survives a failed certbot.

stacks/frost — new stack, segregated from shared sql/rabbitmq:
  - dedicated postgis container (frost-db)
  - dedicated internal mosquitto bus (frost-mosquitto)
  - frost-http + frost-mqtt on a private frost-internal network,
    joined to cloud-app only for nginx ingress at frost.wbd-rd.nl
  - shared mosquitto stack deleted; rabbitmq remains the only public
    MQTT broker (mqtt.wbd-rd.nl:8883 via stream proxy)

stacks/sql — pg_isready healthcheck so keycloak/gitea/mlflow can gate
on service_healthy via cloud-level depends_on overrides.

stacks/nginx-proxy:
  - nginx-init service generates a self-signed bootstrap cert on
    fresh deploy so nginx starts before certbot has issued a real one
  - frost.wbd-rd.nl vhost (/FROST-Server → frost-http:8080,
    /mqtt → frost-mqtt:9876 WebSocket)

stacks/mlflow — custom Dockerfile (upstream + psycopg2-binary) so the
official image can speak to the shared sql backend.

stacks/jupyterhub — DummyAuthenticator stub gated by
JUPYTERHUB_ADMIN_PASSWORD; TODO comments point at OIDC + DockerSpawner.

stacks/rabbitmq — config/{enabled_plugins,rabbitmq.conf} stubs
(management + mqtt plugins, MQTT auth required).

stacks/portainer — ports unpublished; nginx now the only ingress.

stacks/node-red — pin to 4.1 (the floating "4" tag does not exist).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

stacks/frost/README.md

@@ -0,0 +1,42 @@
+# frost
+
+[FROST-Server](https://github.com/FraunhoferIOSB/FROST-Server) — an OGC SensorThings API server. Stores sensors, observations, datastreams in postgis; exposes REST + MQTT.
+
+- **Public hostname**: `frost.wbd-rd.nl`
+  - `/FROST-Server` → REST + admin UI (frost-http:8080)
+  - `/mqtt`         → WebSocket MQTT for SensorThings clients (frost-mqtt:9876)
+- **Networks**: `frost-internal` (private bus) + `app` (nginx ingress)
+- **Backend**: dedicated `postgis/postgis:16-3.4-alpine` container — segregated from the shared `sql` stack
+- **Internal bus**: dedicated `eclipse-mosquitto` for frost-http ↔ frost-mqtt sync (not reachable from outside the stack)
+- **Public MQTT broker for SCADA/IoT clients**: that's `rabbitmq` (port 8883 TLS via nginx stream), NOT this stack
+
+## Volumes (persistent)
+
+- `frost-db-data` — postgis data dir
+- `frost-mosquitto-data`, `frost-mosquitto-log` — internal bus state
+
+Container can be recreated freely; no data loss as long as volumes are kept.
+
+## First-run
+
+1. `docker compose up -d frost-db frost-mosquitto` (or just `up -d` for the full stack — frost-http waits on the db healthcheck)
+2. `frost-http` will auto-create the schema (`persistence_autoUpdateDatabase=true`) on first start
+3. Create the admin user (one-time, post-deploy — the USERS table is created by FROST itself):
+
+   ```bash
+   docker compose exec frost-db psql -U sensorthings -d sensorthings -c \
+     "INSERT INTO \"USERS\" (\"USER_NAME\", \"USER_PASS\") VALUES ('admin', crypt('CHANGE_ME', gen_salt('bf', 12)));"
+   ```
+
+   Subsequent password rotations:
+   ```bash
+   docker compose exec frost-db psql -U sensorthings -d sensorthings -c \
+     "UPDATE \"USERS\" SET \"USER_PASS\"=crypt('NEW_PW', gen_salt('bf', 12)) WHERE \"USER_NAME\"='admin';"
+   ```
+
+## TODO
+
+- Switch from `BasicAuthProvider` to Keycloak OIDC (FROST has a plugin)
+- Bootstrap admin user automatically (post-init container that waits for FROST schema, then runs the SQL above with `${FROST_ADMIN_PASSWORD}`)
+- Document the SensorThings client examples (Things, Datastreams, Observations)
+- pgadmin / db inspection: use shared portainer or a one-off `psql` exec