chore: unify conversation with thread name (#8830)

Done and verified by Codex + refactor feature of RustRover

codex-rs/core/tests/suite/resume_warning.rs

@@ -2,15 +2,15 @@
 
 use codex_core::AuthManager;
 use codex_core::CodexAuth;
-use codex_core::ConversationManager;
-use codex_core::NewConversation;
+use codex_core::NewThread;
+use codex_core::ThreadManager;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::InitialHistory;
 use codex_core::protocol::ResumedHistory;
 use codex_core::protocol::RolloutItem;
 use codex_core::protocol::TurnContextItem;
 use codex_core::protocol::WarningEvent;
-use codex_protocol::ConversationId;
+use codex_protocol::ThreadId;
 use core::time::Duration;
 use core_test_support::load_default_config_for_test;
 use core_test_support::wait_for_event;
@@ -36,7 +36,7 @@ fn resume_history(
     };
 
     InitialHistory::Resumed(ResumedHistory {
-        conversation_id: ConversationId::default(),
+        conversation_id: ThreadId::default(),
         history: vec![RolloutItem::TurnContext(turn_ctx)],
         rollout_path: rollout_path.to_path_buf(),
     })
@@ -56,15 +56,18 @@ async fn emits_warning_when_resumed_model_differs() {
 
     let initial_history = resume_history(&config, "previous-model", &rollout_path);
 
-    let conversation_manager = ConversationManager::with_models_provider(
+    let thread_manager = ThreadManager::with_models_provider(
         CodexAuth::from_api_key("test"),
         config.model_provider.clone(),
     );
     let auth_manager = AuthManager::from_auth_for_testing(CodexAuth::from_api_key("test"));
 
     // Act: resume the conversation.
-    let NewConversation { conversation, .. } = conversation_manager
-        .resume_conversation_with_history(config, initial_history, auth_manager)
+    let NewThread {
+        thread: conversation,
+        ..
+    } = thread_manager
+        .resume_thread_with_history(config, initial_history, auth_manager)
         .await
         .expect("resume conversation");