Merge pull request #12 from T3pp31/codex/update-dependency-version-in-readme

docs: READMEのインストール依存バージョンを1.0.4に更新

Author: T3pp31

README.md

@@ -23,9 +23,11 @@ Add this to your `Cargo.toml`:
 
 ```toml
 [dependencies]
-caesar_cipher_enc_dec = "0.6.2"
+caesar_cipher_enc_dec = "1.0.4"
 ```
 
+> Note: This version is pinned for documentation consistency with this repository (`Cargo.toml`). For the latest release, always check [crates.io](https://crates.io/crates/caesar_cipher_enc_dec).
+
 ## Library Usage
 
 ### Basic Usage