fix(flywheel): correlate REAPI proof runs by request id

[Jess Sullivan (Jesssullivan)]

Summary

• Generate or accept a unique request_id for flywheel-reapi-proof calls.
• Pass that id into the GloriousFlywheel proof workflow and resolve the child run by displayTitle, not by latest timestamp after dispatch.
• Expose the request id as a composite output and add a contract check that prevents timestamp-only correlation from returning.
• Document the concurrency safety boundary.

Dependency

Requires tinyland-inc/GloriousFlywheel#858 to land first so gf-reapi-cell-proof.yml accepts request_id and includes it in the run name.

Validation

• just check
• just flywheel-reapi-proof-contract-check yaml-parse json-parse internal-refs-check endpoint-free-check
• just repo-manifest-validate js-bazel-runner-contract-check
• python3 -m py_compile scripts/validate-ci-templates.py

Refs #45.
Linear: TIN-1777.