Migrate deployment from Vercel to Cloudflare Pages with CI/CD

[Copilot]

Replaces manual Vercel deployment with automated Cloudflare Pages CI/CD. Merges to main now automatically test then deploy.

Summary

• _redirects — added SPA catch-all (/* /index.html 200), replacing the vercel.json rewrite rule
• vercel.json — deleted
• ci.yml — added deploy job gated on test passing, runs only on main pushes via cloudflare/pages-action@v1; uses CLOUDFLARE_API_TOKEN, CLOUDFLARE_ACCOUNT_ID, and GITHUB_TOKEN secrets
• CLAUDE.md — replaced Vercel best-practices block with Cloudflare Pages deploy instructions and one-time setup notes

Pre-requisite (manual, one-time): create the CF Pages project (npx wrangler pages project create fieldops) and add CLOUDFLARE_API_TOKEN + CLOUDFLARE_ACCOUNT_ID as GitHub repo secrets before merging.

Testing

• Ran npm test locally — all tests pass
• Tested manually on fieldops-delta.vercel.app (required for any HaloPSA API changes)
• Added or updated tests for new/changed behavior

Notes

No app code changed — purely infra/config. PWA behavior and Playwright tests are unaffected. The deploy job will silently skip on PR builds (github.event_name != 'push'), so the secrets are only required for production merges.