feat(web-app-chess): add castling.club role with ports, networks, and build setup

- Added network subnet (192.168.103.192/28) and port 8050 for web-app-chess
- Replaced stub README with usability-focused description of castling.club
- Implemented config, vars, meta, and tasks for web-app-chess
- Added Dockerfile, docker-compose.yml, env, and docker-entrypoint.sh templates
- Integrated entrypoint asset placement
- Updated meta to reflect usability and software features

Ref: https://chatgpt.com/share/68b6c65a-3de8-800f-86b2-a110920cd50e

roles/web-app-chess/templates/env.j2

@@ -0,0 +1,16 @@
+# App basics
+APP_SCHEME="{{ 'https' if WEB_PROTOCOL == 'https' else 'http' }}"
+APP_DOMAIN="{{ CHESS_HOSTNAME }}"
+APP_ADMIN_URL="{{ CHESS_ADMIN_URL }}"
+APP_ADMIN_EMAIL="{{ CHESS_ADMIN_EMAIL }}"
+APP_KEY_FILE="/app/data/{{ CHESS_KEY_FILENAME }}"
+APP_HMAC_SECRET="{{ CHESS_HMAC_SECRET }}"
+NODE_ENV="production"
+PORT="{{ container_port }}"
+
+# PostgreSQL (libpq envs)
+PGHOST="{{ database_host }}"
+PGPORT="{{ database_port }}"
+PGDATABASE="{{ database_name }}"
+PGUSER="{{ database_username }}"
+PGPASSWORD="{{ database_password }}"