[BUG] /ultrareview fails with "Claude GitHub app must be installed" despite app being correctly installed

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

The /ultrareview command refuses to launch and claims the Claude GitHub App is not installed, even though the app is installed on the account (bnsa3ed) with explicit access
granted to the target repository (MyPajero-iOS). The error appears regardless of invocation form — no args, branch name, or PR number.

What Should Happen?

/ultrareview should detect the installed GitHub App and launch a cloud review of the feature branch against main.

Error Messages/Logs

Ultrareview cannot launch:                                                                                                                                                      
  The Claude GitHub app must be installed on this repository first.                                                                                                             
  https://github.com/apps/claude/installations/new

Steps to Reproduce

1. Create a private GitHub repo (bnsa3ed/MyPajero-iOS)
2. Install the Claude GitHub App on the bnsa3ed account via https://github.com/apps/claude/installations/new
3. Grant explicit access to MyPajero-iOS under Repository Access
4. Push two branches: main (baseline) and feature/mypajero-phase1-2 (with code)
5. Open PR #1 (feature/mypajero-phase1-2 → main)
6. Run /ultrareview — error appears
7. Run /ultrareview feature/mypajero-phase1-2 — error appears
8. Run /ultrareview 1 (PR number) — error appears
9. Changed Repository Access to "All repositories" — error persists

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.128

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_