ci(pages): self-enable Pages site on first deploy (fix 404)

[jimstratus]

Why

The first Pages deploy on master (run 28018628429) failed, which is why the site 404s. The build step worked (clean published tree), but actions/configure-pages@v5 errored:

Get Pages site failed. Please verify that the repository has Pages enabled
and configured to build using GitHub Actions ... Error: Not Found

GitHub Pages was never enabled on the repo, so there's no Pages site to deploy to.

Fix

Pass enablement: true to actions/configure-pages@v5 so the action creates/enables the Pages site (build type = GitHub Actions) on first run instead of 404ing:

- name: Setup Pages
  uses: actions/configure-pages@v5
  with:
    enablement: true

After merge

On push to master, the workflow should enable Pages and deploy to https://jimstratus.github.io/argus/.

⚠️ Programmatic enablement works on most personal repos but can be blocked by account/org policy. If this run still fails with the same "Not Found", flip Settings → Pages → Source = "GitHub Actions" once and re-run — after that it's permanent.

🤖 Generated with Claude Code

https://claude.ai/code/session_011HG8Axfxjf6rv2mKKDEMxv

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