Add TrustedRouter custom OpenAI client example

[jperla]

Summary

• document TrustedRouter as an OpenAI-compatible routing option
• use https://api.trustedrouter.com/v1 as the base URL
• include the trustedrouter/zdr model alias for privacy-sensitive agent workloads

Why

TrustedRouter is useful for workflows that involve private code, customer data, or other sensitive context. It provides open-source, verifiable attested routing and does not log prompts or outputs by default.

Validation

• git diff --check

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Summary by cubic

Add a runnable TrustedRouter custom client example and document it in the README. Enables privacy-sensitive Stagehand workflows using trustedrouter/zdr via https://api.trustedrouter.com/v1.

• New Features
  • Added packages/core/examples/custom-client-trustedrouter.ts showing CustomOpenAIClient with trustedrouter/zdr and TRUSTEDROUTER_API_KEY.
  • Updated README with a short guide and link to the example.

^{Written for commit 7ddda6c. Summary will update on new commits.}

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Latest commit: 7ddda6c

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[github-actions]

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