[Crypto]: Replace scrypt.c with crypto_scrypt implemented in Rust

[satoshiotomakan]

Description

Fixes: #3391
The problem in the mentioned issue is related to an incorrect working of the scrypt function.
When we compile WalletCore using Xcode 14.3.1 in Release mode, scrypt starts computing weird password hashes. Moreover, it seems to change a global context, so each function call with the same arguments returns a predictable but different hash.

Metrics are provided at #3482 (comment)

How to test

Run C++, Rust, iOS, Android, WASM tests

Types of changes

Add crypto_scrypt FFI function in Rust that is inspired by RustCrypto/scrypt and using RustCrypto/pbkdf2 (most likely not audited) and RustCrypto/salsa20 (not audited, has a usage warning).

Checklist

• Create pull request as draft initially, unless its complete.
• Add tests to cover changes as needed.
• Update documentation as needed.
• If there is a related Issue, mention it in the description.

If you're adding a new blockchain

• I have read the guidelines for adding a new blockchain.

[hewigovens]

We can go with rust this time, have you verified ios release build locally?