Research: map one official harness interface to Adapter Contract v0.1

## Goal Produce a source-backed capability map for **one** planned integration target: OpenAI Codex, Grok, Qwen, or DeepSeek. This is research evidence, not an adapter-support claim. ## Deliverable Add `docs/research/-interface-evidence.md` covering: - official product and interface name; - official documentation or source links and access date; - pinned version, protocol, SDK, or command surface; - transport and authentication method; - mapping to `describe`, `health`, `createSession`, `startRun`, `decideApproval`, `cancel`, `collectArtifacts`, and `close`; - evidence for streaming, approvals, cancellation, resume, steering, artifacts, usage, and platform support; - explicit unknowns and unsupported capabilities; - license, terms, and redistribution constraints; - recommendation: reject, research further, experimental adapter, or adapter proposal. ## Acceptance criteria - [ ] Uses primary/official sources only. - [ ] Separates documented facts, locally verified behavior, and inference. - [ ] Does not scrape an interactive UI or publish credentials/session files. - [ ] Does not claim production support. - [ ] Links to the Adapter Contract and Adapter Catalog. - [ ] `npm run verify` passes and the commit includes DCO sign-off. Comment with the harness you want to investigate so two contributors do not duplicate the same target.