fix: include rollout_path in NewConversationResponse (#3352)

Adding the `rollout_path` to the `NewConversationResponse` makes it so a
client can perform subsequent operations on a `(ConversationId,
PathBuf)` pair. #3353 will introduce support for `ArchiveConversation`.

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[//]: # (BEGIN SAPLING FOOTER)
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* #3353
* __->__ #3352

codex-rs/tui/src/history_cell.rs

@@ -605,6 +605,7 @@ pub(crate) fn new_session_info(
         history_log_id: _,
         history_entry_count: _,
         initial_messages: _,
+        rollout_path: _,
     } = event;
     if is_first_event {
         let cwd_str = match relativize_to_home(&config.cwd) {