Remote Claude Code session (desktop app): GitHubPrManager spawns local `gh` with remote cwd → misleading ENOENT

Summary

When working in a remote Claude Code session in the Claude desktop app (the session's working directory lives on a remote host, reached over SSH), the PR/CI panel reports "CI checks unavailable" for every PR. ~/Library/Logs/Claude/main.log shows:

[GitHubPrManager] Failed to get PR state for branch:
Failed to spawn /opt/homebrew/bin/gh: spawn /opt/homebrew/bin/gh ENOENT

The error message blames the binary path, but /opt/homebrew/bin/gh exists, is executable, and is authenticated. The real failure is the cwd option being passed to child_process.spawn.

Root cause

The remote session's working directory is a remote Linux path, e.g.

Working directory: /home/eo/src/airshelf/.claude/worktrees/charming-wing-4298ff

(visible in ~/Library/Logs/Claude/ssh.log for every RemoteProcess spawn).

The desktop-side GitHubPrManager then tries to populate the PR/CI panel by calling child_process.spawn('/opt/homebrew/bin/gh', [...], { cwd: <that remote path>, env, timeout }) — but on the local macOS host. The remote Linux path doesn't exist on the Mac, posix_spawn fails to chdir into it, and Node surfaces the failure as ENOENT on the binary path, which is misleading enough that users (and the bot in #57859) chase the wrong fix (PATH, LSEnvironment, gh auth, code-signing).

Reproducer (no Claude needed)

node -e 'require("child_process").spawn("/opt/homebrew/bin/gh", ["--version"], {cwd: "/path/that/does/not/exist/locally"}).on("error", e => console.log(e.message, e.code))'
# → spawn /opt/homebrew/bin/gh ENOENT ENOENT

Identical error format to the one in main.log.

Suggested fix

Pick one:

• (a) Preferred: for remote sessions, run gh over SSH against the remote cwd. The remote already has the repo, the branch, and (in this user's case) an authenticated gh. PR state is naturally repo-local; round-tripping to the local host adds nothing.
• (b) Resolve the session cwd to a host-local equivalent before the local spawn — but this only works if the user happens to have the same repo cloned locally at a matching path. Brittle.
• (c) At minimum, detect a non-existent cwd before spawning and surface a clear panel message ("CI checks not available in remote sessions" or "Working directory not found on host") instead of letting the ENOENT bubble up. This would have saved hours of mis-diagnosis.

Versions

• Claude.app: 1.8089.1
• macOS: 26.x (Apple Silicon)
• Remote host: Linux (Ubuntu), reached via SSH
• gh: 2.92.0 (Homebrew, /opt/homebrew/bin/gh), keyring-authed