Consider adding [Language] at the beginning of the captions

The majority will be the same language the book is in, but some are static listings that are meant to be copied and pasted directly. This may create confusion.

Adding the programming language used in the listing may help

Look at the ebook's source files for code listings and captions. Identify where captions are generated or written. Add the programming language name at the start of relevant captions, likely in markdown or a build script. Verify changes by building the ebook locally to ensure formatting is correct.

索引モデルが issue の本文から書いたものです。