[App-server] v2 for account/updated and account/logout (#6175)

V2 for `account/updated` and `account/logout` for app server. correspond
to old `authStatusChange` and `LogoutChatGpt` respectively. Followup PRs
will make other v2 endpoints call `account/updated` instead of
`authStatusChange` too.

codex-rs/app-server-protocol/src/protocol/v1.rs

@@ -400,6 +400,7 @@ pub struct SessionConfiguredNotification {
 
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]
 #[serde(rename_all = "camelCase")]
+/// Deprecated notification. Use AccountUpdatedNotification instead.
 pub struct AuthStatusChangeNotification {
     pub auth_method: Option<AuthMode>,
 }