Return user-facing message if API reuturn 429 API rate limit reached #2202 (#10415)

* Return user-facing message if API reuturn 429 API rate limit reached

* clarify the error message

* fix(agents): improve 429 user messaging (#10415) (thanks @vincenthsin)

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Co-authored-by: Peter Steinberger <steipete@gmail.com>

src/agents/pi-embedded-runner/run/attempt.ts

@@ -733,6 +733,8 @@ export async function runEmbeddedAttempt(
         onAssistantMessageStart: params.onAssistantMessageStart,
         onAgentEvent: params.onAgentEvent,
         enforceFinalTag: params.enforceFinalTag,
+        config: params.config,
+        sessionKey: params.sessionKey ?? params.sessionId,
       });
 
       const {