docs(wasm-utxo): update feature matrix in README.md

Mark FixedScript Wallet Transaction Support for Bitcoin and Litecoin
as complete in the feature status table.

Issue: BTC-2656

Co-authored-by: llm-git <[email protected]>

Author: OttoAllmendinger

packages/wasm-utxo/README.md

@@ -20,7 +20,7 @@ This project is under active development.
 | Descriptor Wallet: Address Support      | ✅ Complete | 🚫          | 🚫          | 🚫          | 🚫          | 🚫          | 🚫          |
 | Descriptor Wallet: Transaction Support  | ✅ Complete | 🚫          | 🚫          | 🚫          | 🚫          | 🚫          | 🚫          |
 | FixedScript Wallet: Address Generation  | ✅ Complete | ✅ Complete | ✅ Complete | ✅ Complete | ✅ Complete | ✅ Complete | ✅ Complete |
-| FixedScript Wallet: Transaction Support | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     |
+| FixedScript Wallet: Transaction Support | ✅ Complete | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     | ⏳ TODO     | ✅ Complete | ⏳ TODO     |
 
 ## Building