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## 2.11.1

**`(fix):`** Normalize the architecture label in the structured `User-Agent` (emitted when
`includePlatformHeaders` is enabled) so the 64-bit x86 aliases (`x64`,
`amd64`, `x86_64`) all report as the canonical `x86_64`, keeping the value
consistent across generators.

## 2.11.0

**`(feat):`** Add opt-in support for a structured `User-Agent` header on generated SDK
clients, gated behind a new `includePlatformHeaders` config option (default
off, so existing generated output is unchanged). When enabled, the client
reports its SDK name/version plus the operating system, architecture, and PHP
runtime version in the Twilio-style shape
`{sdkName}/{sdkVersion} ({os}; {arch}) PHP/{runtimeVersion}`
(e.g. `my-sdk/1.0.0 (linux; x86_64) PHP/8.2.0`). The platform values are
resolved at runtime via `PHP_OS`, `php_uname('m')`, and `PHP_VERSION`. Unknown
segments are omitted gracefully (the `(os; arch)` group is dropped when both are
empty, a single known value is included on its own, and the version suffix is
dropped when unavailable), and the discrete `X-Fern-Platform` / `X-Fern-Runtime`
headers are consolidated into the `User-Agent`.