Add production deployment pipeline

[alanw707]

Summary

• Add PR quality/security workflow with lint, build, PHP syntax, dependency review, Gitleaks, CodeQL, and production dependency audit
• Add production deploy workflow that reuses scripts/deploy-theme.sh with GitHub Secrets
• Document required production secrets/environment setup
• Include hero panel width adjustment and repo hygiene ignores

Verification

• npm run lint:css
• npm run lint:js
• npm run build
• PHP syntax check
• npm audit --omit=dev --audit-level=moderate

Deployment notes / rollback

• Merge to main triggers the new Deploy Production workflow.
• Production secrets must exist in the GitHub production environment before deploy can complete.
• Rollback by reverting this PR or rerunning a previous known-good deployment.

[github-advanced-security]

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