fix: restore applyPrepareMessages call after agentcrumbs strip

Author: ericallam

packages/trigger-sdk/src/v3/ai.ts

@@ -3191,7 +3191,7 @@ function chatAgent<
 
                     runResult = await userRun({
                       ...restWire,
-                      messages: messagesForRun,
+                      messages: await applyPrepareMessages(accumulatedMessages, "run"),
                       clientData,
                       continuation,
                       previousRunId,