Initial: build-deploy-game.yml reusable workflow

Drives the standard four-stage build-api-core → deploy-api-core → build-web
→ deploy-web pipeline for a played game. Game repos invoke via:

  jobs:
    deploy:
      uses: played/workflows/.gitea/workflows/build-deploy-game.yml@main
      with:
        game-id: <slug>
      secrets: inherit

The caller's BUILD_ENV / NPMRC / REGISTRY_* / PLAYED_* /
STEP_CA_PROVISIONER_PASSWORD are inherited; `game-id` parameterizes the
VM paths (~/<id>, ~/<id>-secrets) and the docker tag context.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -0,0 +1 @@
+.DS_Store