feat: add external access via Cloudflare DDNS

Add cloudflare-ddns container for automatic DNS updates, update game
server connection strings to use play.consultoria-as.com, and document
port forwarding and external access setup.

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

docker/docker-compose.dev.yml

@@ -67,13 +67,22 @@ services:
     ports:
       - "3000:3000"
 
+  cloudflare-ddns:
+    image: favonia/cloudflare-ddns:latest
+    restart: unless-stopped
+    environment:
+      CF_API_TOKEN: ${CF_API_TOKEN}
+      DOMAINS: ${PUBLIC_HOST:-play.consultoria-as.com}
+      PROXIED: "false"
+      IP6_PROVIDER: none
+
   openfusion:
     build:
       context: ../servers/openfusion
       dockerfile: Dockerfile
     restart: unless-stopped
     environment:
-      SHARD_IP: ${OPENFUSION_SHARD_IP:-192.168.10.234}
+      SHARD_IP: ${PUBLIC_HOST:-192.168.10.234}
       MOTD: ${OPENFUSION_MOTD:-Bienvenido a Project Afterlife - FusionFall Academy}
     ports:
       - "23000:23000"