Add standards-as-code guardrails

[Kristopherlb]

Summary

• add an in-repository RAC corpus with three Scout requirements standards and two accepted architecture decisions
• pin RAC 0.22.0 with a fully hash-locked dependency graph and generate drift-checked agent guidance
• map every normative requirement to deterministic CI evidence or an explicit human-review procedure
• enforce recursive dependency direction, cycles, the scoring-log entry point, and the standards CI execution contract
• complete the public project rename from LFD Evals to Scout in project-facing metadata and documentation

Verification

• 111 unit and end-to-end tests pass locally
• 22 negative/positive standards regression tests pass
• Ruff and Mypy pass
• ShellCheck and Python compile checks pass
• python3 tools/ci_checks.py all passes
• python3 tools/ci_checks.py public-release passes
• python3 tools/check_standards.py all passes
• rac gate rac/ passes with zero advisories
• generated agent guidance drift check passes
• clean Python 3.12 install from standards/rac-requirements.lock succeeds with required hashes

[Kristopherlb]

Superseded by a rebased branch after main advanced with #1 and the Pages field guide. No commits or remote branches were deleted.