[BUG] /ultrareview blocked: GitHub access fails on PR mode, repo too large for no-arg mode

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?

Body to paste:
## Summary
/ultrareview is unusable for me on a private monorepo on the Claude Max plan. Both invocation modes fail and there's no UI path I can find to fix the underlying GitHub authorization.

## Environment

• CLI version: 2.1.126
• Plan: Claude Max
• OS: macOS (Darwin 25.4.0)
• Repo: private monorepo, ~21K LoC diff in current PR
• Branch: feat/react-19-next-16-migration → main (PR exists, OPEN)

## Repro

1. /ultrareview <PR#> → Ultrareview could not start the remote session: GitHub repository access check failed — re-authorize GitHub in settings
2. /ultrareview (no arg) → Repo is too large. Push a PR and use /ultrareview <PR#> instead.

So the only viable mode (PR mode) is blocked by the auth error, and the suggested fallback (no-arg mode) is blocked by repo size. There is no working path.

## What I tried

• claude auth logout + claude auth login (fresh session) — no change
• Settings → Connectors → GitHub Integration: shows "Connected" — no change
• Settings → Claude Code → enabled "Create pull requests automatically" toggle — no change
• claude.ai/code: cloud environment shows the repo correctly attached (checkmark in repo picker) — but CLI still fails
• Settings → Claude Code → Authorization tokens: ALL tokens have only user:* scopes (file_upload, inference,

mcp_servers, profile, sessions:claude_code). No repo or github scope on any token. No "Connect GitHub for Claude Code" UI surfaced anywhere.

## Hypothesis
/ultrareview PR-mode needs a GitHub-scoped token attached to my Claude account, but no UI path exists to grant it.
The "GitHub Integration" connector under Settings → Connectors appears to be for chat sessions only and doesn't grant the scope /ultrareview needs.

## Ask
Either expose the GitHub-scope grant UI (Settings → Claude Code section), or have /ultrareview trigger the OAuth flow directly when the auth check fails.

What Should Happen?

it should have connected

Error Messages/Logs

Steps to Reproduce

tried multiple times

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.126 (Claude Code

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_