[REVIEW] gcp-review: add BigQuery authorized view, Pub/Sub push auth, and Cloud Run invoker/IAP gates

[JamesJi79]

Adds three review gates for gcp-review skill:

1. BigQuery Authorized View Policy Drift Gate (closes [REVIEW] gcp-review: add BigQuery authorized view policy drift gates #2674)

   • Effective data access path audit check
   • Policy tag consistency check

2. Pub/Sub Push Authentication Audience Replay Gate (closes [REVIEW] gcp-review: add Pub/Sub push auth audience replay gates #2673)

   • OIDC token audience scope check
   • Message deduplication and idempotency check

3. Cloud Run Invoker and IAP Effective Path Gate (closes [REVIEW] gcp-review: add Cloud Run invoker and IAP effective path gates #2672)

   • Effective ingress path verification check
   • Invoker IAM inheritance audit check

All three gates add evidence requirements for common GCP false-positive patterns.

[github-actions]

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