what changed

• adds an extension cdp url example in browser configuration page

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Summary by cubic

Documents the extensionCdpUrl browser option in the configuration page with TypeScript, Python, and Go examples, showing how to give the extension its own CDP WebSocket URL when the client connects through a proxy or gateway. The examples use a token-based gateway URL, and the docs also cover validation rules and the fallback behavior when the option is omitted. Using a separate endpoint keeps the gateway URL and its credentials out of the extension and avoids routing the extension's CDP commands through the gateway.