Add safety check notification and error handling (#19055)

Adds a new app-server notification that fires when a user account has
been flagged for potential safety reasons.

codex-rs/mcp-server/src/codex_tool_runner.rs

@@ -263,7 +263,9 @@ async fn run_codex_tool_session_inner(
                         outgoing.send_response(request_id.clone(), result).await;
                         break;
                     }
-                    EventMsg::Warning(_) | EventMsg::GuardianWarning(_) => {
+                    EventMsg::Warning(_)
+                    | EventMsg::GuardianWarning(_)
+                    | EventMsg::ModelVerification(_) => {
                         continue;
                     }
                     EventMsg::GuardianAssessment(_) => {