Add SLH-DSA to Rust wrapper

[c16a]

Description

This pull request adds Rust wrappers for SLH-DSA

Testing

Added tests in Rust wrapper

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[wolfSSL-Bot]

Can one of the admins verify this patch?

[dgarske]

Hi @c16a, thank you for your contribution! Can you tell us more about your project and if you plan to submit any additional PR's? We do require a signed contributor agreement to accept third-party code. See https://github.com/wolfSSL/wolfssh/blob/master/CONTRIBUTING.md for details on setting that up.
Thanks, David Garske, wolfSSL

[github-actions]

MemBrowse Memory Report

No memory changes detected for:

• gcc-arm-cortex-m0plus
• gcc-arm-cortex-m3
• gcc-arm-cortex-m4
• gcc-arm-cortex-m4-baremetal
• gcc-arm-cortex-m4-crypto-only
• gcc-arm-cortex-m4-dtls13
• gcc-arm-cortex-m4-min-ecc
• gcc-arm-cortex-m4-openssl-compat
• gcc-arm-cortex-m4-pkcs7
• gcc-arm-cortex-m4-pq
• gcc-arm-cortex-m4-rsa-only
• gcc-arm-cortex-m4-sp-math
• gcc-arm-cortex-m4-tls12
• gcc-arm-cortex-m4-tls13
• gcc-arm-cortex-m7
• gcc-arm-cortex-m7-pq
• gcc-arm-cortex-m7-tls13
• linuxkm-pie
• linuxkm-standard
• stm32-sim-stm32h753

[c16a]

Hey @dgarske, I'm working on Arx, an opensource software security module (with plans of eventually turning it into a HSM installation).

I'm exploring the option of using wolfCrypto as the underlying crypto provider and I've noticed that some Rust wrappers are missing in the PQ implementations, and I wanted to contribute them upstream.

Yes, I do plan to contribute any Arx-related wolfCrypto improvements to the wolfSSL mainline if they seem appropriate for general purpose.

I'm working on the contributor agreement while this gets reviewed.