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/files/docker-entrypoint.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+APP_KEY_FILE="${APP_KEY_FILE}"
+APP_KEY_PUB="${APP_KEY_FILE}.pub"
+
+# 1) Generate signing key pair if missing
+if [[ ! -f "${APP_KEY_FILE}" || ! -f "${APP_KEY_PUB}" ]]; then
+  echo "[chess] generating RSA signing key pair at ${APP_KEY_FILE}"
+  /app/tools/gen-signing-key.sh "${APP_KEY_FILE}"
+fi
+
+# 2) Wait for PostgreSQL if env is provided
+if [[ -n "${PGHOST:-}" ]]; then
+  echo "[chess] waiting for PostgreSQL at ${PGHOST}:${PGPORT}..."
+  until pg_isready -h "${PGHOST}" -p "${PGPORT}" -U "${PGUSER}" >/dev/null 2>&1; do
+    sleep 1
+  done
+fi
+
+# 3) Run migrations (idempotent)
+echo "[chess] running migrations"
+yarn migrate up
+
+# 4) Start app
+echo "[chess] starting server on port ${PORT}"
+exec yarn start