Log SDK version on REST calls

[clintfred]

As an IronCore audit log user
I want to know what SDK and version make a request to the IronCore service

• so that SDKs with specific behaviors/defects can be recognized and isolated
• so that I can tell if there are out of date clients making requests for encrypted data

AC:

• Every REST request to the IronCore service should include a header X-IronCore-Sdk-Version. Values of the header should be of the form ironoxide <MAJOR>.<MINOR>.<PATCH> and should match the current version of the SDK sending the request.
• This header should be visible at the ironcore service and should be logged to the requests audit trail

This looks like a promising path: https://doc.rust-lang.org/cargo/reference/environment-variables.html