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/exec/src/event_processor_with_human_output.rs

@@ -523,6 +523,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     history_log_id: _,
                     history_entry_count: _,
                     initial_messages: _,
+                    rollout_path: _,
                 } = session_configured_event;
 
                 ts_println!(