fix: correct PushToolResult type in integration test

Author: Zoo (VP)

src/core/assistant-message/__tests__/error-interceptor-guided-format.integration.spec.ts

@@ -8,6 +8,7 @@ import { getTaskErrorState } from "../../tools/error-interception"
 import { NativeToolCallParser } from "../NativeToolCallParser"
 
 import type { Task } from "../../task/Task"
+import type { ToolResponse } from "../../../shared/tools"
 
 // ---------------------------------------------------------------------------
 // Integration test: REAL ToolErrorInterceptor + REAL NativeToolCallParser
@@ -316,8 +317,8 @@ describe("Error Interceptor Guided Format Integration — INVALID_JSON_ARGUMENTS
 				task as unknown as object,
 				{
 					handleError: vi.fn(),
-					pushToolResult: (content: string) => {
-						capturedResults.push(content)
+					pushToolResult: (content: ToolResponse) => {
+						capturedResults.push(typeof content === "string" ? content : JSON.stringify(content))
 					},
 				},
 				{