feat: add Cardano wallet extension helpers

[GiMa-SwapKit]

Summary

Adds Cardano wallet extension helpers under @swapkit/wallet-extensions/cardano.

Includes support for:

• CIP-30 browser wallet discovery, enable/connect, signTx, signData, and submitTx
• CIP-8 message signing through CIP-30 signData
• CIP-45 QR/deep-link P2P connection URI helpers and transport adapter
• CIP-158 mobile wallet browser deep links

Usage

import { createCardanoDappClient } from "@swapkit/wallet-extensions/cardano";

const cardano = await createCardanoDappClient({
  walletId: "nami",
});

const address = await cardano.getAddress();
const signature = await cardano.signMessage("Login to my dApp");
const signedTx = await cardano.signTransaction(unsignedTxCborHex, true);

Tests

• bun test packages/wallet-extensions/test/cardano-extensions.test.ts
• bun run --filter './packages/wallet-extensions' type-check