v0.7.0

Changed

• Publish the next-phase interoperability delivery as repository v0.7.0:
  cumulative-layer migration/rollback guidance, the pinned non-normative
  OpenTelemetry companion, tested retry projections and hosted MkDocs docs.
• Align current documentation, sibling references, package metadata and the
  portable-suite snapshot with v0.7.0. Suite cases and expected outcomes are
  unchanged. Repository v0.6.2 was published with an undersized patch version;
  the incorrect v0.6.2 release and tag have been removed.
• Run/Workflow markers remain 0.4-draft and provenance remains 0.6-draft.
  This repository release introduces no 0.7-draft schema family and closes
  no independent-review gates. No sibling runtime dependency bump is needed.