[Bitcoin]: Refactor PSBT protocol

[satoshiotomakan]

Description

We decided to refactor BitcoinV2.SigningInput to have either a TransactionBuilder or Psbt. This allows to pass PSBT signing input to AnySigner.sign and AnySigner.plan.

How to test

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

Types of changes

• Move most of the fields from BitcoinV2.SigningInput to BitcoinV2.TransactionBuilder
• Add BitcoinV2.SigningInput.transaction one of TransactionBuilder or Psbt
• Remove BitcoinPsbt module

Checklist

• [x] Create pull request as draft initially, unless its complete.
• [x] Add tests to cover changes as needed.
• [x] Update documentation as needed.
• [x] 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[bot]]

Binary size comparison

➡️ aarch64-apple-ios:

- 12.14 MB
+ 12.13 MB   -7 KB

➡️ aarch64-apple-ios-sim:

- 12.15 MB
+ 12.14 MB   -7 KB

➡️ aarch64-linux-android:

- 15.58 MB
+ 15.57 MB   -11 KB

➡️ armv7-linux-androideabi:

- 13.30 MB
+ 13.29 MB   -9 KB

➡️ wasm32-unknown-emscripten:

- 11.04 MB
+ 11.03 MB   -8 KB