chore: merge name and title (#17116)

Merge title and name concept to leverage the sqlite title column and
have more efficient queries

---------

Co-authored-by: Codex <noreply@openai.com>

codex-rs/rollout/src/policy.rs

@@ -97,6 +97,7 @@ fn event_msg_persistence_mode(ev: &EventMsg) -> Option<EventPersistenceMode> {
         | EventMsg::AgentReasoning(_)
         | EventMsg::AgentReasoningRawContent(_)
         | EventMsg::TokenCount(_)
+        | EventMsg::ThreadNameUpdated(_)
         | EventMsg::ContextCompacted(_)
         | EventMsg::EnteredReviewMode(_)
         | EventMsg::ExitedReviewMode(_)
@@ -142,7 +143,6 @@ fn event_msg_persistence_mode(ev: &EventMsg) -> Option<EventPersistenceMode> {
         | EventMsg::AgentReasoningSectionBreak(_)
         | EventMsg::RawResponseItem(_)
         | EventMsg::SessionConfigured(_)
-        | EventMsg::ThreadNameUpdated(_)
         | EventMsg::McpToolCallBegin(_)
         | EventMsg::WebSearchBegin(_)
         | EventMsg::ExecCommandBegin(_)
@@ -188,8 +188,10 @@ fn event_msg_persistence_mode(ev: &EventMsg) -> Option<EventPersistenceMode> {
 mod tests {
     use super::EventPersistenceMode;
     use super::should_persist_event_msg;
+    use codex_protocol::ThreadId;
     use codex_protocol::protocol::EventMsg;
     use codex_protocol::protocol::ImageGenerationEndEvent;
+    use codex_protocol::protocol::ThreadNameUpdatedEvent;
 
     #[test]
     fn persists_image_generation_end_events_in_limited_mode() {
@@ -206,4 +208,17 @@ mod tests {
             EventPersistenceMode::Limited
         ));
     }
+
+    #[test]
+    fn persists_thread_name_updates_in_limited_mode() {
+        let event = EventMsg::ThreadNameUpdated(ThreadNameUpdatedEvent {
+            thread_id: ThreadId::new(),
+            thread_name: Some("saved-session".to_string()),
+        });
+
+        assert!(should_persist_event_msg(
+            &event,
+            EventPersistenceMode::Limited
+        ));
+    }
 }