fix(acceptance): 兼容只读压测容器报告

验收模拟器 Pod 使用只读根文件系统，失败报告缓冲不能依赖 mktemp。改为在 Shell 内存中捕获并回放压测 JSON，同时保留原始退出状态。\n\n验证：bash -n、ShellCheck、远端脚本语法检查、git diff --check。

scripts/cluster/run-production-acceptance.sh

@@ -710,13 +710,11 @@ export AI_GATEWAY_ACCEPTANCE_RUN_TOKEN=$(decode "$run_token_b64")
 export AI_GATEWAY_ACCEPTANCE_GEMINI_MODEL=$(decode "$gemini_model_b64")
 export AI_GATEWAY_ACCEPTANCE_VIDEO_MODEL=$(decode "$video_model_b64")
 export AI_GATEWAY_ACCEPTANCE_REAL_IMAGE_URLS=$(decode "$image_urls_b64")
-report_file=$(mktemp)
-trap '\''rm -f -- "$report_file"'\'' EXIT
 set +e
-/app/easyai-ai-gateway-acceptance-load -profile "$1" >"$report_file"
+report=$(/app/easyai-ai-gateway-acceptance-load -profile "$1")
 status=$?
 set -e
-cat "$report_file"
+printf "%s\n" "$report"
 exit "$status"
 '
   {