temporarily disable private desktop until it works with elevated IPC path (#14986)

codex-rs/windows-sandbox-rs/src/elevated/command_runner_win.rs

@@ -294,7 +294,7 @@ fn spawn_ipc_process(
             &req.env,
             stdin_mode,
             StderrMode::Separate,
-            req.use_private_desktop,
+            false,
         )?;
         (
             pipe_handles.process,