feat: implement OSX file copy & paste

Signed-off-by: ClSlaid <cailue@bupt.edu.cn>

src/server/connection.rs

@@ -479,7 +479,7 @@ impl Connection {
                         ipc::Data::RawMessage(bytes) => {
                             allow_err!(conn.stream.send_raw(bytes).await);
                         }
-                        #[cfg(any(target_os="windows", target_os="linux"))]
+                        #[cfg(any(target_os="windows", target_os="linux", target_os = "macos"))]
                         ipc::Data::ClipboardFile(clip) => {
                             allow_err!(conn.stream.send(&clip_2_msg(clip)).await);
                         }