Part of #1486. Depends on the flip issue.

Sweep user/contributor docs and godoc for the new domain, and record the migration + transition policy.

• docs/**, README.md — every aicr.nvidia.com reference (apiVersion examples, label/annotation/attestation docs)
• Package godoc examples (pkg/recipe/doc.go, pkg/snapshotter/doc.go, pkg/cli/doc.go, pkg/build/doc.go, etc.)
• Update docs/design/011-artifact-apiversion-policy.md to record the domain change and the dual-accept transition window
• Re-run make bom-docs if image/BOM output references the host

Acceptance criteria

• No stale aicr.nvidia.com in docs/**, README.md, or godoc (except intentional historical/transition notes)
• Design doc 011 records the migration + window
• Anchor-link hygiene preserved (lychee clean)
• make qualify green