build: stop publishing the host port under Coolify

Coolify attaches the container to its proxy network and routes to the exposed
port, so the host publish was redundant and additionally reachable on
0.0.0.0:3000 outside TLS. Left commented for standalone `docker compose up`.

renderer/compose.yml

@@ -10,8 +10,10 @@ services:
       RENDER_TIMEOUT_MS: "${RENDER_TIMEOUT_MS:-15000}"
       MAX_OPTIONS: "${MAX_OPTIONS:-32}"
       MAX_OPTION_CHARS: "${MAX_OPTION_CHARS:-40}"
-    ports:
-      - "${PORT:-3000}:${PORT:-3000}"
+    # Coolify routes to the container port over its proxy network, so the host
+    # port stays unpublished there. Uncomment for a standalone `docker compose up`.
+    # ports:
+    #   - "${PORT:-3000}:${PORT:-3000}"
     healthcheck:
       test: ["CMD-SHELL", "node -e \"fetch('http://127.0.0.1:${PORT:-3000}/api/healthz').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))\""]
       interval: 30s