Merge pull request #10 from xt0x/docs/update-readme

Update project overview and clean up directory structure

Author: xt0x

README.md

@@ -10,7 +10,7 @@
 
 ---
 
-# Project Overview
+## Project Overview
 
 This repository provides the following capabilities for English BIP39 mnemonics:
 
@@ -184,7 +184,6 @@ This repository includes tests for:
 
 ```text
 .
-├── docs/                             # Specifications and implementation plans
 ├── src/main/java/com/example/bip39/
 │   ├── api/                          # Public API
 │   ├── bit/                          # Bit-level helpers