feat: add Dockerfile + app service for production deploy

Adds a production Docker image (node:20-alpine) and an `app` service in
docker-compose.yml so the Next.js app can run as a long-lived container
instead of just build/test in ephemeral containers. Requires `apk add
openssl` before `npm ci`, otherwise Prisma silently picks the wrong query
engine binary on Alpine and only fails at runtime. Also wires
AUTH_TRUST_HOST=true, required by Auth.js when running behind the NPM
reverse proxy.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

docker-compose.yml

@@ -1,4 +1,17 @@
 services:
+  app:
+    build: .
+    container_name: asset-license-mgmt-app
+    env_file:
+      - .env
+    ports:
+      - "3002:3000"
+    depends_on:
+      - db
+    restart: unless-stopped
+    networks:
+      - asset-license-mgmt
+
   db:
     image: postgres:16-alpine
     container_name: asset-license-mgmt-db