Add Traefik reverse proxy configuration with Docker provider

Set up Traefik v3.2 with Docker label-based routing, Let's Encrypt SSL certificates, and configuration examples for multiple services including dashboard, Nextcloud, Portainer, and other applications.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

docker-compose.yml

@@ -0,0 +1,31 @@
+services:
+  traefik:
+    image: traefik:v3.2
+    container_name: traefik
+    restart: unless-stopped
+    network_mode: host
+    security_opt:
+      - no-new-privileges:true
+    ports:
+      - "80:80"
+      - "443:443"
+    environment:
+      - DOCKER_API_VERSION=1.44
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+      - ./traefik.yml:/etc/traefik/traefik.yml:ro
+      - ./acme.json:/acme.json
+    networks:
+      - traefik-net
+    labels:
+      - "traefik.enable=true"
+      - "traefik.http.routers.traefik-dashboard.rule=Host(`${DASHBOARD_HOST}`)"
+      - "traefik.http.routers.traefik-dashboard.entrypoints=websecure"
+      - "traefik.http.routers.traefik-dashboard.service=api@internal"
+      - "traefik.http.routers.traefik-dashboard.tls.certresolver=letsencrypt"
+      - "traefik.http.routers.traefik-dashboard.middlewares=traefik-auth"
+      - "traefik.http.middlewares.traefik-auth.basicauth.users=${DASHBOARD_USER}:${DASHBOARD_PASSWORD}"
+
+networks:
+  traefik-net:
+    external: false