fix: default to credits from ChatGPT auth, when possible (#1971)

Uses this rough strategy for authentication:

```
if auth.json
	if auth.json.API_KEY is NULL # new auth
		CHAT
	else # old auth
		if plus or pro or team
			CHAT
		else 
			API_KEY
		
else OPENAI_API_KEY
```

---
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* __->__ #1971
* #1970
* #1966
* #1965
* #1962

codex-rs/tui/src/history_cell.rs

@@ -537,8 +537,8 @@ impl HistoryCell {
                 lines.push(Line::from("  • Signed in with ChatGPT"));
 
                 let info = tokens.id_token;
-                if let Some(email) = info.email {
-                    lines.push(Line::from(vec!["  • Login: ".into(), email.into()]));
+                if let Some(email) = &info.email {
+                    lines.push(Line::from(vec!["  • Login: ".into(), email.clone().into()]));
                 }
 
                 match auth.openai_api_key.as_deref() {
@@ -549,9 +549,8 @@ impl HistoryCell {
                     }
                     _ => {
                         let plan_text = info
-                            .chatgpt_plan_type
-                            .as_deref()
-                            .map(title_case)
+                            .get_chatgpt_plan_type()
+                            .map(|s| title_case(&s))
                             .unwrap_or_else(|| "Unknown".to_string());
                         lines.push(Line::from(vec!["  • Plan: ".into(), plan_text.into()]));
                     }