checks: generate CIMC support from release notes

[monrog2]

Summary

• add a release-time scraper for model-specific CIMC support in Cisco APIC release notes
• embed generated support data in the standalone validator so APIC execution remains deterministic and offline
• resolve the APIC-L3/M3 CIMC 4.1(1g) false failure reported in CIMC 4.1.1g and ACI 6.1.5e validation fails #435
• add parser safeguards, regression coverage, and maintainer workflow documentation

Scraper safeguards

• normalizes dotted and parenthesized CIMC versions
• maps every APIC model group named in shared release-note entries
• excludes explicitly deferred releases
• rejects unexpected unqualified CIMC entries
• enforces expected models and minimum version counts per model to detect incomplete source changes
• provides --check mode for release preparation

Validation

• python3 -m pytest -q: 1059 passed
• Python compilation passed
• live scraper freshness check passed
• git diff --check passed

Fixes #435

[monrog2]

Integration Test Summary

The integration pipeline completed with a failed status.

• Python compatibility tests passed.
• The new CIMC compatibility validation ran across all available test artifacts.
• Of 111 validation results:
  • 68 passed
  • 43 failed
    • 33 identified a CIMC-version compatibility issue requiring remediation before upgrade.
    • 10 required manual review because the target version or compatibility data was unavailable.

The reported failures fall into three categories:

1. CIMC version below the recommended level — the validation identifies APIC server platforms whose installed CIMC version is below the catalog recommendation. Some cases include a multi-step CIMC upgrade warning.
2. Upgrade sequencing restriction — certain platform/version combinations require the APIC to be upgraded to a supported fixed release before upgrading CIMC, to avoid a known upgrade issue.
3. Insufficient compatibility input or catalog data — a small set of results requires manual verification because the requested target version was not supplied or no compatibility entry exists for that platform/target-release combination.

The results demonstrate that the PR's CIMC release-note support produces structured pass, failure, and manual-review outcomes, including actionable remediation guidance.