use zed_extension_api::{self as zed, Result}; struct HaskellExtension; impl zed::Extension for HaskellExtension {    fn new() -> Self {        Self    }     fn language_server_command(        &mut self,        _config: zed::LanguageServerConfig,        worktree: &zed::Worktree,    ) -> Result<zed::Command> {        let path = worktree            .which("haskell-language-server-wrapper")            .ok_or_else(|| "hls must be installed via ghcup".to_string())?;         Ok(zed::Command {            command: path,            args: vec!["lsp".to_string()],            env: Default::default(),        })    }} zed::register_extension!(HaskellExtension);