Improve Chapter 31 reading path

[jules-tth]

Summary

• Rewrites the Chapter 31.11 recommended-reading page as a practical methodology and governance study path.
• Covers local truth, DevOps, SRE, ITSM, policy/compliance/audit, incident response, legal/licensing sources, professional communities, source evaluation, a reading notebook, and a four-week practice path.

Duplicate prevention

• Verified PR Improve Chapter 31 resources lesson #292 is the canonical Chapter 31 organizations/conferences/resources slice.
• Final target-file overlap check returned no open PR touching docs/lessons/31_methodology_policy_and_politics/31.11_recommended_reading.md immediately before PR creation.

Verification

• python3 -m mkdocs build --strict
• git diff --check
• make build