Progress on MS extension support

[Firstyear]

Add support for MS OAPXBC key management in the soft-tpm, with a view to have this work with HW TPM's.

Checklist

• [ x ] This pr contains no AI generated code
• [ x ] cargo fmt has been run
• [ x ] cargo clippy has been run and there's no issues
• [ x ] cargo test has been run and passes

[dmulder]

Lgtm

[dmulder]

@Firstyear I don't have rights to merge, so you'll need to push the button yourself.

[dmulder]

FYI, I'm using your sealing code to prevent the release of the PRT:
himmelblau-idm/libhimmelblau@dd548ed
Technically a client with the TPM secrets could decrypt it, but I'm not enabling it. This way the PRT is a black box, that can be stashed in a database, then retrieved and passed to msal for authenticating later.

[Firstyear]

@dmulder I don't know how I overlooked that, I gave you maintainer access now.