feat(XRP): Add support for signing a raw JSON transaction

[satoshiotomakan]

Description

Add support for signing a raw JSON transaction, in particular, swap.

Types of changes

• Add SigningInput.rawJson string. If set, SigningInput.operationOneof is ignored
• Add XRPLTypes::STArray and XRPLTypes::STObject

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:

- 13.50 MB
+ 13.54 MB 	 +37 KB

➡️ aarch64-apple-ios-sim:

- 13.50 MB
+ 13.54 MB 	 +37 KB

➡️ aarch64-linux-android:

- 17.72 MB
+ 17.77 MB 	 +56 KB

➡️ armv7-linux-androideabi:

- 14.89 MB
+ 14.93 MB 	 +42 KB

➡️ wasm32-unknown-emscripten:

- 12.58 MB
+ 12.62 MB 	 +46 KB

[gupnik]

👍