[TON]: Add CryptoBoxSecretKey FFIs to create from Bytes, get Bytes

[satoshiotomakan]

Description

Add CryptoBoxSecretKey.isValid(Data), CryptoBoxSecretKey(Data), CryptoBoxSecretKey.data()

How to test

Run Rust, iOS, Android, C++ tests

Types of changes

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.

[github-actions]

Binary size comparison

➡️ aarch64-apple-ios:

- 12.02 MB
+ 12.02 MB 	 +3 KB

➡️ aarch64-apple-ios-sim:

- 12.02 MB
+ 12.03 MB 	 +2 KB

➡️ aarch64-linux-android:

- 15.39 MB
+ 15.39 MB 	 +4 KB

➡️ armv7-linux-androideabi:

- 13.16 MB
+ 13.16 MB 	 +3 KB

➡️ wasm32-unknown-emscripten:

- 10.89 MB
+ 10.90 MB 	 +3 KB