Get queued session detail for cloud runners

Lets a cloud runner-in-box (e2b/modal/daytona) fetch its session detail from the platform rather than the local daemon control API (`127.0.0.1:7734/api/daemon/sessions/:id`), which does not exist inside a cloud sandbox. The provisioner stamps `DONMAI_DAEMON_URL=<platform-url>` into the box's env so `donmai agent run` fetches its detail here. Source of truth is the Redis `work:items` hash. The full payload is available **only while the session is still QUEUED** - it is deleted on claim. Auth: bearer worker token (runtime JWT or legacy `WORKER_API_KEY`). The response includes `authToken`, system prompts, repo URL, and org ID - not readable without authentication.

curl -X GET "https://example.com/api/daemon/sessions/string"

{
  "sessionId": "string",
  "issueId": "string",
  "issueIdentifier": "string",
  "priority": 0,
  "queuedAt": 0,
  "prompt": "string",
  "providerSessionId": "string",
  "workType": "research",
  "sourceSessionId": "string",
  "projectName": "string",
  "repository": "string",
  "kits": {},
  "platformUrl": "http://example.com",
  "organizationId": "string",
  "linearSessionId": "string"
}

{
  "error": "Session not found"
}

{
  "error": "Session not found"
}

{
  "error": "Session not found"
}