fix(traefik): point docker provider network at cameleer-traefik

The static config set `provider.docker.network: cameleer`, but no network
by that literal name exists. The `cameleer` network defined in the
compose file gets namespaced by compose to `cameleer_cameleer`, and
managed app containers created at runtime only ever attach to
`cameleer-traefik` (per `DockerNetworkManager.TRAEFIK_NETWORK`).

Symptom: when the Docker provider's preferred network doesn't match any
network on a container, Traefik picks an arbitrary container IP and may
route to one on a bridge Traefik itself isn't attached to — requests
hang until Traefik's upstream timeout fires (504 Gateway Timeout).

Fix is one line: match the network that `cameleer-server` actually
attaches its managed containers to.

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

docker/cameleer-traefik/traefik.yml

@@ -18,6 +18,6 @@ providers:
   docker:
     endpoint: "unix:///var/run/docker.sock"
     exposedByDefault: false
-    network: cameleer
+    network: cameleer-traefik
   file:
     filename: /etc/traefik/dynamic.yml