use std::env;use std::fs;use std::path::PathBuf; fn main() -> Result<(), Box<dyn std::error::Error>> {    copy_extension_api_rust_files()} /// rust-analyzer doesn't support include! for files from outside the crate./// Copy them to the OUT_DIR, so we can include them from there, which is supported.fn copy_extension_api_rust_files() -> Result<(), Box<dyn std::error::Error>> {    let out_dir = env::var("OUT_DIR")?;    let input_dir = PathBuf::from("../extension_api/wit");    let output_dir = PathBuf::from(out_dir);     println!("cargo:rerun-if-changed={}", input_dir.display());     for entry in fs::read_dir(&input_dir)? {        let entry = entry?;        let path = entry.path();        if path.is_dir() {            println!("cargo:rerun-if-changed={}", path.display());             for subentry in fs::read_dir(&path)? {                let subentry = subentry?;                let subpath = subentry.path();                if subpath.extension() == Some(std::ffi::OsStr::new("rs")) {                    let relative_path = subpath.strip_prefix(&input_dir)?;                    let destination = output_dir.join(relative_path);                     fs::create_dir_all(destination.parent().unwrap())?;                    fs::copy(&subpath, &destination)?;                }            }        } else if path.extension() == Some(std::ffi::OsStr::new("rs")) {            let relative_path = path.strip_prefix(&input_dir)?;            let destination = output_dir.join(relative_path);             fs::create_dir_all(destination.parent().unwrap())?;            fs::copy(&path, &destination)?;            println!("cargo:rerun-if-changed={}", path.display());        }    }     Ok(())}