* feat: support OpenRouter API key in config
* fixup: dedupe openrouter_api_key vs master, drop no-op compile-guard test
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Co-authored-by: Garry Tan <garrytan@gmail.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>