Add Open Studio portfolio SOTA context

[gchahal1982]

Summary

• add unscored Open Studio portfolio context rather than a seventh product verdict
• map relationships to the six audited products, current comparator landscape, evidence boundaries, gaps, and roadmap
• correct release-evidence, access-restriction, and pinned-commit provenance wording after independent review

Testing

• Rust workspace with Cargo 1.97.1 — passed; one hardware-backed video fixture ignored
• platform contracts/proofline/package checks — passed
• Aura IDE Kit — 12/12 passed
• standalone Node contract set — 34 passed, 4 sibling-flagship integration cases unavailable because expected sibling repositories are absent
• preserved pre-existing Docusaurus generated artifacts byte-for-byte and excluded them

An earlier testing subagent was attempted but failed with An internal error occurred. Please try again. If this issue persists, please contact support. The bounded local replacement validation above completed. Hosted/native OS/hardware/release-service paths remain unverified as stated in the context dossier.

[vorflux]

Superseded by #5, which contains the equivalent documentation diff on a clean branch with signed commit 7e3027e7afb3374354654a1ae2f442ff146c0f50. The replacement passes the local DCO verifier; this PR's unsigned commit cannot satisfy the required DCO check.