Add per-turn cyber access program selection (#40687)

## What changed

- Add the experimental `turn/start.cyberAccessProgram` option with `standard`,
  `daybreakBlue`, and `daybreakRed` values.
- Forward the selection as `access_programs.cyber` on Responses, WebSocket,
  and remote-compaction requests made with ChatGPT authentication, while
  omitting it for API-key and custom-provider requests.
- Preserve the per-turn selection across recovery, compaction, and child-agent
  turns without making it a persistent thread setting.

## Testing

- Cover app-server forwarding, authentication boundaries, WebSocket reuse,
  turn recovery, compaction, and child-agent inheritance.

GitOrigin-RevId: d2eb468f365b2214c5099bc21741cf30f8bd2eb5