Conversation naming (#8991)

Session renaming:
- `/rename my_session`
- `/rename` without arg and passing an argument in `customViewPrompt`
- AppExitInfo shows resume hint using the session name if set instead of
uuid, defaults to uuid if not set
- Names are stored in `CODEX_HOME/sessions.jsonl`

Session resuming:
- codex resume <name> lookup for `CODEX_HOME/sessions.jsonl` first entry
matching the name and resumes the session

---------

Co-authored-by: jif-oai <jif@openai.com>

codex-rs/tui/src/chatwidget/tests.rs

@@ -134,6 +134,7 @@ async fn resumed_initial_messages_render_history() {
     let configured = codex_core::protocol::SessionConfiguredEvent {
         session_id: conversation_id,
         forked_from_id: None,
+        thread_name: None,
         model: "test-model".to_string(),
         model_provider_id: "test-provider".to_string(),
         approval_policy: AskForApproval::Never,
@@ -200,6 +201,7 @@ async fn replayed_user_message_preserves_text_elements_and_local_images() {
     let configured = codex_core::protocol::SessionConfiguredEvent {
         session_id: conversation_id,
         forked_from_id: None,
+        thread_name: None,
         model: "test-model".to_string(),
         model_provider_id: "test-provider".to_string(),
         approval_policy: AskForApproval::Never,
@@ -252,6 +254,7 @@ async fn submission_preserves_text_elements_and_local_images() {
     let configured = codex_core::protocol::SessionConfiguredEvent {
         session_id: conversation_id,
         forked_from_id: None,
+        thread_name: None,
         model: "test-model".to_string(),
         model_provider_id: "test-provider".to_string(),
         approval_policy: AskForApproval::Never,
@@ -823,6 +826,7 @@ async fn make_chatwidget_manual(
         current_status_header: String::from("Working"),
         retry_status_header: None,
         thread_id: None,
+        thread_name: None,
         forked_from: None,
         frame_requester: FrameRequester::test_dummy(),
         show_welcome_banner: true,