Group of 2 Under the hood
Bedrock/Mantle requests now send an additional shared header block.
Outgoing requests to the Bedrock and Mantle providers, as well as the Anthropic API client, now merge in a new Cv() header block on top of the existing Em() headers.
This applies across all auth code paths: API key, skip-auth, profile bearer, AWS bearer-token, and credential-chain paths in Anthropic client construction.