fix(reusable-fix): propagate gh pr view failures in eligibility check

[rh-hemartin]

Summary

• gh pr view in the "Check fix eligibility" step was called with 2>/dev/null || echo '{"labels":[],"author":""}', silently swallowing API failures
• A failed call returned empty author/labels, causing the step to exit 1 with a misleading "Human-authored PR without fullsend-fix label" message instead of exposing the real error
• Removes the silent fallback; failure now emits ::error:: and exits 1 explicitly

Closes #1564

Test plan

• Verify the eligibility step passes normally on a bot-triggered PR with expected labels
• Simulate a gh pr view failure (e.g. revoke token) and confirm the job fails with ::error::Failed to fetch PR info rather than the misleading "human-authored" message

🤖 Generated with Claude Code

[github-actions]

Site preview

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Commit: d969b5675d1a3a20305e6fcc7a8ed6111fa5e2b9

[fullsend-ai-review]

Review

Findings

Medium

• [protected-path] .github/workflows/reusable-fix.yml — This PR modifies a file under .github/, which is a protected path requiring human approval. The change is well-justified (fixes silent error suppression per reusable-fix: gh pr view failure silently bypasses fix eligibility check #1564) and tightly scoped, but human sign-off is required regardless of correctness.

Info

• [style-consistency] .github/workflows/reusable-fix.yml:250 — The new error handling pattern (|| { echo "::error::..."; exit 1; }) is consistent with similar patterns elsewhere in this workflow (e.g., the fix-commit counting step uses || { echo "::warning::..."; ... }). The escalation from ::warning:: (soft failure with fallback) to ::error:: (hard failure) is appropriate here since eligibility is a gate, not a best-effort count. No action needed.