Fix tests

Author: jahooma

packages/agent-runtime/src/run-agent-step.ts

@@ -293,10 +293,18 @@ export const runAgentStep = async (
     try {
       nResponses = JSON.parse(responsesString) as string[]
       if (!Array.isArray(nResponses)) {
+        if (params.n > 1) {
+          throw new Error(
+            `Expected JSON array response from LLM when n > 1, got non-array: ${responsesString.slice(0, 50)}`,
+          )
+        }
         // If it parsed but isn't an array, treat as single response
         nResponses = [responsesString]
       }
     } catch (e) {
+      if (params.n > 1) {
+        throw e
+      }
       // If parsing fails, treat as single raw response (common for n=1)
       nResponses = [responsesString]
     }