ci: claude-review + claude-security-review workflows infra-fail instantly (0-1s, cost 0) on every attempt

[kyle-sexton]

What's wrong

On PR #1118, both automated-review workflows errored within 0-1s on all attempts across three pushes (runs 29991269948, 29991270012, 29992407577, 29992407492, 29992820840, 29992824027), each posting Claude encountered an error + the infra-status warning. Last SDK result each time: {"subtype":"success","is_error":true,"num_turns":1,"duration_ms":<1000,"total_cost_usd":0} — the SDK call fails before doing any work (auth/config/entrypoint class, not a review verdict).

The review / review and security-review / security-review gate CHECKS still pass, so PRs read fully green while the actual reviews never run — the gates measure infra completion, not review completion.

Acceptance criteria

• Root cause identified from the run logs (auth token, model id, action version, or entrypoint)
• Reviews complete end-to-end on a test PR
• Decide + implement: should the infra-status warning also fail (or pend) the gate check, so green means reviewed

Blocked by

None — can start immediately.

[kyle-sexton]