Add NATS-over-WebSocket compose for Coolify

Configures a single NATS 2.10 service exposing a WebSocket listener on
:8080 (no_tls; Traefik terminates TLS at nats.volcanic.tes.gd) with
env-driven username/password auth and a persisted JetStream store.

.gitignore

@@ -0,0 +1 @@
+deploy.json

CLAUDE.md

@@ -0,0 +1,122 @@
+# NATS Expert
+
+This project deploys a NATS server behind Coolify, reachable **over WebSockets** only. NATS' native TCP port (4222) is not exposed to the outside — the WS endpoint is the sole entry point for both applications and the managing agent.
+
+## Deployment target
+
+- **Coolify project:** `Volcanic MFEs` (`p4fts5a0kv3tahzjtbtfequk`)
+- **Server:** `localhost` (`d0c4owww4kwo0ow08wws4ss8`)
+- **Build pack:** `dockercompose`
+- **Compose file:** `/docker-compose.yml`
+- **Public domain:** `https://nats.volcanic.tes.gd` → routed by Traefik to `nats:8080` (WebSocket listener)
+- **TLS:** terminated at Traefik. NATS itself runs with `no_tls: true` on the WS listener.
+
+Coolify's non-secret app config (project/server UUIDs, name, domain) lives in `deploy.json` at the repo root and is **gitignored** — it is regenerated locally when needed by the `deploying-to-coolify-via-api` skill flow.
+
+## Connection details (for agents managing this NATS)
+
+Both are populated from the two env vars set on the Coolify application:
+
+- `NATS_USER` — admin username (default: `admin`)
+- `NATS_PASSWORD` — admin password (generated at deploy time, stored in the Coolify app's env vars)
+
+The current live values are printed by:
+
+```bash
+: "${COOLIFY_URL:?}" "${COOLIFY_KEY:?}"
+APP_UUID=$(jq -r '.app.uuid' deploy.json)   # from local deploy.json
+curl -sS -H "Authorization: Bearer $COOLIFY_KEY" \
+  "$COOLIFY_URL/api/v1/applications/$APP_UUID/envs" \
+  | jq -r '.[] | select(.is_preview==false) | "\(.key)=\(.value)"'
+```
+
+If `deploy.json` is not present, list applications under the Volcanic MFEs project and find the one named `nats`:
+
+```bash
+curl -sS -H "Authorization: Bearer $COOLIFY_KEY" \
+  "$COOLIFY_URL/api/v1/projects/p4fts5a0kv3tahzjtbtfequk" \
+  | jq '.applications[] | {uuid, name}'
+```
+
+### WebSocket URL
+
+```
+wss://nats.volcanic.tes.gd
+```
+
+The NATS server accepts standard NATS-over-WebSocket framing (RFC 6455 with the `nats` subprotocol). No custom path; connect to the root URL.
+
+### With `nats` CLI
+
+```bash
+nats \
+  --server=wss://nats.volcanic.tes.gd \
+  --user="$NATS_USER" --password="$NATS_PASSWORD" \
+  server info
+```
+
+### With `nats.js` / `nats.ws` (Node/browser)
+
+```js
+import { connect } from 'nats.ws'; // browser
+// import { connect } from 'nats';  // node with ws
+
+const nc = await connect({
+  servers: 'wss://nats.volcanic.tes.gd',
+  user: process.env.NATS_USER,
+  pass: process.env.NATS_PASSWORD,
+});
+```
+
+### With `nats-py`
+
+```python
+import asyncio, os
+from nats.aio.client import Client as NATS
+
+async def main():
+    nc = NATS()
+    await nc.connect(
+        servers=['wss://nats.volcanic.tes.gd'],
+        user=os.environ['NATS_USER'],
+        password=os.environ['NATS_PASSWORD'],
+    )
+    await nc.publish('hello', b'world')
+    await nc.drain()
+
+asyncio.run(main())
+```
+
+## What's inside the server
+
+- **Listeners**
+  - `4222` — native NATS protocol, `expose`d only inside the compose network. Not reachable from outside.
+  - `8080` — WebSocket listener, `no_tls: true`. Traefik terminates TLS and forwards `ws://nats:8080` from the public `wss://nats.volcanic.tes.gd`.
+  - `8222` — HTTP monitoring (`/healthz`, `/varz`, `/jsz`), internal only. Used by the compose healthcheck.
+- **JetStream**: enabled, persisted to the named volume `nats-data` mounted at `/data`. Limits: 256MB memory / 4GB file. Bump `max_file_store` in `nats-server.conf` if you need more.
+- **Auth**: a single user, whose name and password come from the `NATS_USER` / `NATS_PASSWORD` env vars via NATS' native `$VAR` substitution in the config. No accounts, no operator/JWT mode.
+
+## Managing / redeploying
+
+Config or compose changes → commit and push to `main`, then trigger a Coolify deploy (fire-and-forget):
+
+```bash
+: "${COOLIFY_URL:?}" "${COOLIFY_KEY:?}"
+APP_UUID=$(jq -r '.app.uuid' deploy.json)   # or look it up as shown above
+curl -sS -X POST "$COOLIFY_URL/api/v1/deploy?uuid=$APP_UUID" \
+  -H "Authorization: Bearer $COOLIFY_KEY"
+# → { "deployments": [ { "deployment_uuid": "…" } ] }   done, don't poll
+```
+
+Rotating the password: PATCH the `NATS_PASSWORD` env on the Coolify app, then redeploy. Do not edit `nats-server.conf` — auth is env-driven.
+
+To add a second user (e.g. a scoped app account), edit the `authorization.users` array in `nats-server.conf`, wire the new credential env vars into `docker-compose.yml`, and set them in Coolify.
+
+## Files in this repo
+
+| File | Purpose |
+|---|---|
+| `docker-compose.yml` | Single `nats` service, exposes 4222/8080/8222 internally; only 8080 is routed publicly via `SERVICE_FQDN_NATS_8080` + Coolify's `docker_compose_domains`. |
+| `nats-server.conf` | NATS config: JetStream, WebSocket listener (`no_tls`), env-driven auth. |
+| `.gitignore` | Keeps `deploy.json` out of git. |
+| `deploy.json` (local only) | Coolify app config used by the `deploying-to-coolify-via-api` skill. |

docker-compose.yml

@@ -0,0 +1,24 @@
+services:
+  nats:
+    image: nats:2.10-alpine
+    restart: unless-stopped
+    command: ["-c", "/etc/nats/nats-server.conf"]
+    environment:
+      - SERVICE_FQDN_NATS_8080
+      - NATS_USER=${NATS_USER}
+      - NATS_PASSWORD=${NATS_PASSWORD}
+    volumes:
+      - ./nats-server.conf:/etc/nats/nats-server.conf:ro
+      - nats-data:/data
+    expose:
+      - "4222"
+      - "8080"
+      - "8222"
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://localhost:8222/healthz"]
+      interval: 30s
+      timeout: 5s
+      retries: 3
+
+volumes:
+  nats-data:

nats-server.conf

@@ -0,0 +1,21 @@
+server_name: "nats-volcanic"
+
+port: 4222
+http_port: 8222
+
+jetstream {
+  store_dir: "/data"
+  max_memory_store: 256MB
+  max_file_store: 4GB
+}
+
+websocket {
+  port: 8080
+  no_tls: true
+}
+
+authorization {
+  users = [
+    { user: $NATS_USER, password: $NATS_PASSWORD }
+  ]
+}