fix: skip OpenAI rebuild for anthropic clients

[pranjalbhatia710]

Summary

• Skip shared OpenAI client rebuilds for native anthropic_messages clients
• Add regression coverage so Bedrock/Anthropic native paths do not try to create an OpenAI client during stale-stream cleanup

Validation

• ./scripts/run_tests.sh tests/run_agent/test_run_agent.py
• git diff --check

Fixes #36693

[mxnstrexgl]

🤖 Automated PR Review

Security Scan

• ✓ No hardcoded secrets, injection sinks, unsafe deserialization, or dependency red flags found by this automated scan.

Code Quality

• ✓ No blocking code-quality issues found by this automated scan.

Summary

Status: APPROVE — security findings: 0, quality suggestions: 0.

Automated review; raw diff content intentionally omitted.

[alt-glitch]

Duplicate of #36719 and #36714 — all three fix #36693 (stale-stream watchdog rebuilding the OpenAI client for anthropic_messages/Bedrock). Also overlaps the broader stream-cleanup PRs #28240/#33855. Maintainers should pick one canonical fix.

[pranjalbhatia710]

Thanks for flagging this. Agree that this overlaps the other stale-stream watchdog fixes for #36693. I’ll leave this PR as a narrow candidate, but I’m fine with maintainers picking the earliest/canonical branch and closing this one if that keeps the queue cleaner.

[pranjalbhatia710]

Closing this to reduce maintainer queue noise after the duplicate/consolidation note above. Thanks for pointing me to the earlier canonical PRs.