Made token refresh code resilient to missing id_token (#5782)

This PR does the following:
1. Changes `try_refresh_token` to handle the case where the endpoint
returns a response without an `id_token`. The OpenID spec indicates that
this field is optional and clients should not assume it's present.
2. Changes the `attempt_stream_responses` to propagate token refresh
errors rather than silently ignoring them.
3. Fixes a typo in a couple of error messages (unrelated to the above,
but something I noticed in passing) - "reconnect" should be spelled
without a hyphen.

This PR does not implement the additional suggestion from @pakrym-oai
that we should sign out when receiving `refresh_token_expired` from the
refresh endpoint. Leaving this as a follow-on because I'm undecided on
whether this should be implemented in `try_refresh_token` or its
callers.

codex-rs/core/src/codex.rs

@@ -1911,7 +1911,7 @@ async fn run_turn(
                     // at a seemingly frozen screen.
                     sess.notify_stream_error(
                         turn_context.as_ref(),
-                        format!("Re-connecting... {retries}/{max_retries}"),
+                        format!("Reconnecting... {retries}/{max_retries}"),
                     )
                     .await;