feat: add Docker Compose production stack with Traefik + Logto

7-service stack: Traefik (reverse proxy), PostgreSQL (shared),
Logto (identity), cameleer-saas (control plane), cameleer3-server
(observability), ClickHouse (traces). ForwardAuth middleware for
tenant-aware routing to cameleer3-server.

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

traefik.yml

@@ -0,0 +1,14 @@
+api:
+  dashboard: false
+
+entryPoints:
+  web:
+    address: ":80"
+  websecure:
+    address: ":443"
+
+providers:
+  docker:
+    endpoint: "unix:///var/run/docker.sock"
+    exposedByDefault: false
+    network: cameleer