web-app-chess: refactor runtime & entrypoint

- Move entrypoint to files/ and deploy via copy
- Parameterize APP_KEY_FILE, data dir, and entrypoint paths
- Require explicit PORT/PG envs (remove fallbacks)
- Drop stray header from config/main.yml
- Dockerfile: use templated data dir & entrypoint; keep node user
- Compose: set custom image, adjust volume mapping
- env: derive APP_SCHEME from WEB_PROTOCOL; NODE_ENV from ENVIRONMENT
- tasks: add 01_core and simplify main to include it

Ref: https://chatgpt.com/share/68b851c5-4dd8-800f-8e9e-22b985597b8f

roles/web-app-chess/templates/docker-compose.yml.j2

@@ -6,15 +6,13 @@
       args:
         CHESS_REPO_URL: "{{ CHESS_REPO_URL }}"
         CHESS_REPO_REF: "{{ CHESS_REPO_REF }}"
-    image: "castling_custom"
+    image: "{{ CHESS_CUSTOM_IMAGE }}"
     container_name: "{{ CHESS_CONTAINER }}"
     hostname: "{{ CHESS_HOSTNAME }}"
-    environment:
-      - NODE_ENV=production
     ports:
       - "127.0.0.1:{{ ports.localhost.http[application_id] }}:{{ container_port }}"
     volumes:
-      - 'data:/app/data'
+      - 'data:{{ CHESS_APP_DATA_DIR }}'
     env_file:
       - .env
 {% include 'roles/docker-container/templates/healthcheck/curl.yml.j2' %}