chore: sync repository quality assets

[lightning-it-shared-assets-sync]

Automated sync from lightning-it/shared-assets-lit.

This PR updates:

• Lightning IT release-model metadata and documentation
• repository-quality workflow
• guarded Renovate automerge workflow and policy
• fail-closed Copilot review gate and review instructions
• trusted Codex-to-Copilot remediation workflow and prompt
• exact-head human or MLX-90 Security promotion authorization
• private-safe OpenSSF Scorecard workflow
• repository-quality validation scripts

This bootstrap PR targets develop. Once
develop exists and is protected, normal sync PRs target develop.

[lightning-it-shared-assets-sync]

{"app_id":4351516,"schema":"lit-shared-assets-sync-provenance/v2","source_job":"Sync repository-quality assets to documentation","source_repository":"lightning-it/shared-assets-lit","source_run_attempt":1,"source_run_id":34765679172,"source_run_url":"https://github.com/lightning-it/shared-assets-lit/actions/runs/34765679172","source_sha":"23e962290a670451a961d1358c18519b97754339","source_workflow":".github/workflows/sync-repository-quality-repos.yml","target_base_sha":"5bbd578868fc4d37efdf0b101c57e5a18cf66907","target_head_sha":"2c62c2531df4cc13f6cd56d4d81847650b5cad9b","target_pr":345,"target_repository":"lightning-it/documentation","target_tree_sha":"029142b85c3aca553253f63d420dd282d97f8d8a"}

[lightning-it-shared-assets-sync]

Superseded by #346, the newer verified run-bound synchronization PR. The immutable source branch is retained as evidence.