feat: add v2 encrypt/decrypt support to WRW flows

[bdesoky]

Ticket: WCN-172

This pull request refactors key decryption logic across multiple coin modules to use the asynchronous decryptAsync method instead of the synchronous decrypt method. Additionally, it updates the Web Crypto usage in encryptV2.ts to ensure compatibility with both browser and Node.js environments by using the correct subtle crypto implementation. These changes improve security, performance, and compatibility.

Key Decryption Refactor

Migration to async decryption:

• Replaces all instances of this.bitgo.decrypt with await this.bitgo.decryptAsync for user and backup key decryption in the following coins and modules:
  • Abstract Ethereum-like coins and tokens (abstractEthLikeNewCoins.ts, ethLikeToken.ts, erc20Token.ts, erc721Token.ts, avaxc.ts, eth.ts, etc.ts) [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]
  • Substrate-based coins (abstractSubstrateCoin.ts, dot.ts, polyx.ts) [1] [2] [3] [4] [5] [6]
  • Other coins: Ada, Algo, Hbar, Iota, Near [1] [2] [3] [4] [5] [6] [7]

Crypto Compatibility Improvements

Web Crypto subtle selection:

• Updates encryptV2.ts to use a subtle variable that references either the browser's crypto.subtle or Node's webcrypto.subtle, ensuring compatibility across environments. All cryptographic operations (importKey, deriveKey, encrypt, decrypt) now use this unified reference. [1] [2] [3] [4] [5]

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These changes modernize the codebase to use asynchronous cryptography APIs, which is essential for non-blocking operations, and ensure that cryptographic functions work seamlessly in both browser and Node.js contexts.

WRW Local Test

Tested by wiring the modules from local BitGoJs (with these changes) into WRW. A HTETH wallet was created in staging with encryptionVersion: 2. Before these changes, the following error would appear when attempting to use the WRW:

With the changes wired up:

Screen.Recording.2026-05-21.at.5.47.35.PM.mov

[linear-code]

WCN-172