Add mitigation-derived ATT&CK exploration

[wan0net]

Summary

• ingest pinned Enterprise ATT&CK 19.2 mitigations, techniques, relationships, and procedure evidence
• assess the September 2026 ISM against ATT&CK mitigations with candidate/review lifecycle and protect/detect/recover classification
• add mitigation-derived ATT&CK detail to ISM controls
• add a top-level Navigator-inspired ATT&CK catalogue with technique, mitigation, and reviewed-control traversal

Data boundary

• controls map only to mitigations; techniques are reached through official MITRE relationships
• candidate and rejected ISM mappings remain hidden from public queries
• the shipped corpus currently contains 599 candidate mappings and zero reviewed mappings

Verification

• pnpm verify
• 80 ingestion tests
• 199 web tests
• deterministic database build and validation
• 12 static routes
• 7 Chromium desktop/phone tests with accessibility checks