ci(workflows): standardize Node.js 24 across all CI workflows

[WilliamBerryiii]

Summary

Standardize Node.js version across all GitHub Actions workflows to Node.js 24, ensuring compatibility with cspell 10.0.0 and other modern npm packages that require Node.js ≥22.18.0.

Background

PR #342 (Dependabot cspell 9.7.0 → 10.0.0) fails in the Documentation Lint / Docs Lint check because cspell 10.0.0 depends on import-fresh v4.0.0, which requires Node.js ≥22.15. The CI runner (ubuntu-latest / Ubuntu 24.04) ships Node.js 20.x by default.

An audit of all 28 workflow files found:

• 3 workflows missing setup-node entirely (relying on runner default Node 20.x)
• 2 workflows pinned to Node 18
• 1 workflow already on Node 22.x

Changes

Workflow	Change
docs-lint.yml	Added setup-node with Node 24
code-quality-lint.yml	Added setup-node with Node 24
security-scan.yml	Added setup-node with Node 24
pages-deploy.yml	Upgraded Node 18 → 24
docs-automation.yml	Upgraded Node 18 → 24 (2 jobs)
cluster-test-terraform.yml	Upgraded Node 22.x → 24

All setup-node steps use the pinned SHA actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v4.3.0.

Acceptance Criteria

• All CI workflows use Node.js 24
• All 28 workflow files pass YAML validation
• PR chore(deps)(deps): bump cspell from 9.7.0 to 10.0.0 #342 (cspell 10.0.0) can merge after this lands