fix(app-server): for external auth, replace id_token with chatgpt_acc… (#11240)

…ount_id and chatgpt_plan_type

### Summary
Following up on external auth mode which was introduced here:
https://github.com/openai/codex/pull/10012

Turns out some clients have a differently shaped ID token and don't have
a chosen workspace (aka chatgpt_account_id) encoded in their ID token.
So, let's replace `id_token` param with `chatgpt_account_id` and
`chatgpt_plan_type` (optional) when initializing the external ChatGPT
auth mode (`account/login/start` with `chatgptAuthTokens`).

The client was able to test end-to-end with a Codex build from this
branch and verified it worked!

codex-rs/login/src/server.rs

@@ -20,7 +20,7 @@ use codex_core::auth::AuthDotJson;
 use codex_core::auth::save_auth;
 use codex_core::default_client::originator;
 use codex_core::token_data::TokenData;
-use codex_core::token_data::parse_id_token;
+use codex_core::token_data::parse_chatgpt_jwt_claims;
 use rand::RngCore;
 use serde_json::Value as JsonValue;
 use tiny_http::Header;
@@ -548,7 +548,7 @@ pub(crate) async fn persist_tokens_async(
     let codex_home = codex_home.to_path_buf();
     tokio::task::spawn_blocking(move || {
         let mut tokens = TokenData {
-            id_token: parse_id_token(&id_token).map_err(io::Error::other)?,
+            id_token: parse_chatgpt_jwt_claims(&id_token).map_err(io::Error::other)?,
             access_token,
             refresh_token,
             account_id: None,