Revert "rebase"

This reverts commit 9ad5c1386f, reversing
changes made to 4b9e6f4383.

codex-rs/app-server/tests/suite/v2/initialize.rs

@@ -248,7 +248,6 @@ async fn turn_start_notify_payload_includes_initialize_client_name() -> Result<(
                 text: "Hello".to_string(),
                 text_elements: Vec::new(),
             }],
-            submission_type: None,
             ..Default::default()
         })
         .await?;