[Bug] Auto-update install failure not surfacing error details in /doctor output

Bug Description
Issue: Auto-update install failing on native install (darwin-arm64).

Diagnostics:

• Running: native 2.1.178 (commit d4d9538afb0f)
• Path: /Users/mmichalski/.local/share/claude/versions/2.1.178
• Config install method: native
• Auto-updates: enabled, channel latest
• Last update attempt: failed (install_failed) — 2026-06-16
• Stable: 2.1.153 / Latest: 2.1.178

What I'd expect: auto-update either succeeds or surfaces why it failed. Right now /doctor just shows install_failed with no error code, log path, or remediation hint. Running 2.1.178 already, so it's not blocking me, but the persistent warning triangle with no actionable detail is the bug.

Ask: expose the failure reason inline in /doctor, or point at a log file (~/.local/share/claude/logs/...?) where the install error is captured.

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.178
• Feedback ID: 3bf2a52f-9b60-4791-9f8a-d41a2994cfa9

Errors

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