What
When Claude Code reads a file's content, character encoding, or line-ending style, it now opens the file using the await using syntax. This is a JavaScript feature for explicit resource management, meaning the file handle is automatically and reliably closed once the operation finishes, rather than being closed manually in the code. The actual work of reading and decoding the file has also been moved into a dedicated helper function instead of being handled inline.
Why
This is an internal reliability improvement: automatic cleanup of file handles reduces the chance of resource leaks if an error occurs partway through reading a file. It should not change what Claude Code shows you, only make file reading more robust under the hood.