Persist upstream Radar review artifacts

[yvette-carlisle]

Summary

• Refresh the deterministic openai/codex upstream review queue.
• Add source-backed upstream reviews and impact classifications for PRs 26449, 26450, 26552, and 26631.
• Add social_candidate/v1 handoffs for PRs 26450, 26552, and 26631 only; no social_post/v1 records and no X publication.
• Add rebuilt github_change_bundle/v1 artifacts for the four reviewed PRs.

Reviewed subjects

• feat(remote-control): add pairing status transport openai/codex#26449: remote-control pairing status transport; impact watch, no social candidate.
• feat(app-server): add remote control pairing status RPC openai/codex#26450: experimental app-server remoteControl/pairing/status RPC; social candidate.
• Make runtime workspace roots absolute in app-server API openai/codex#26552: app-server runtimeWorkspaceRoots absolute path contract; social candidate.
• Add JSON output for plugin subcommands openai/codex#26631: JSON output for plugin and marketplace subcommands; social candidate.

Validation

• jq empty over the 11 hand-authored review/impact/candidate JSON files.
• candidate_text lengths checked: 184, 193, and 191 chars.
• cargo run -p decodex --bin decodex -- radar bundle validate artifacts/github/bundles/openai-codex-pr-26449.json artifacts/github/bundles/openai-codex-pr-26450.json artifacts/github/bundles/openai-codex-pr-26552.json artifacts/github/bundles/openai-codex-pr-26631.json
• cargo run -p decodex --bin decodex -- radar validate
• cargo make check-site-content
• git diff --cached --check

Boundaries

• No push to main.
• No Linear mutation.
• No social_post/v1 artifact.
• No X publish action.