Add Docker healthcheck to docker-compose.yml

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -6,6 +6,12 @@ services:
       - "traefik.enable=true"
       - "traefik.http.routers.cadcad-staging.rule=Host(`cadcad-staging.jeffemmett.com`)"
       - "traefik.http.services.cadcad.loadbalancer.server.port=3000"
+    healthcheck:
+      test: ["CMD", "wget", "--no-verbose", "--tries=1", "--spider", "http://127.0.0.1:3000/"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 15s
     networks:
       - traefik-public