ops: establish official/evidence/collateral structure and migrate docs from yai

[francescomaiomascio]

Goal: make yai-ops the canonical home for official documents + evidence bundles + field collateral.

Scope:

• Create clean repo layout: official/, evidence/, collateral/
• Migrate from yai/docs:
  • 40-qualification -> evidence/qualification
  • 40-qualification/WAVES -> evidence/waves
  • 50-validation -> evidence/validation
  • 70-reports -> evidence/reports
  • 80-commercial -> collateral/
• Add governance + publishing rules.
• Add CANONICAL note for SC102-WAVE1-LAUNCH.

Acceptance:

• yai-ops has readable top-level structure (not numeric export)
• Evidence is append-only; official docs are release-only
• Collateral is separated and references wave baselines