Add support for Timing-Allow-Origin header

### Problem Statement

[Timing-Allow-Origin](https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Timing-Allow-Origin) is not currently supported by the plugin and left as an exercise to the user.

### Proposed Solution

Support generating this header.

### Alternatives Considered

_No response_

### Scope

Core timing (filter/interceptor)

### Additional Context

_No response_