SnowCat 雪猫底层全源码：NapCat 4.18.28 底座 + SnowLuma 能力移植 + V8 通道适配 9.9.37

26 包 monorepo（TS 全源码）：
- snowcat-core: NT 内核 API 封装 + listener（含 9.9.37 六回调适配）+ Packet 发包
- snowcat-onebot: OneBot v11 全动作 + MCP Streamable HTTP 适配器 + 稳定线
- snowcat-webui-frontend/backend: 雪猫控制台（React+HeroUI）
- snowcat-shell: 单文件 bundle 出口（vite inlineDynamicImports）
- snowcat-native: napi2native / MoeHoo / ffmpeg / pty 运行时
- 56 项 SnowLuma 独门动作移植（qzone 全家桶/群相册/装扮/闪照/收藏）
- 工具件: 解包器/启动器/便携制作器/doctor

GitHub 关联已全量指向 DandanLLab/SnowCatQQ

packages/snowcat-onebot/action/stream/TestStreamDownload.ts

@@ -0,0 +1,43 @@
+import { ActionName } from '@/snowcat-onebot/action/router';
+import { OneBotAction, OneBotRequestToolkit } from '@/snowcat-onebot/action/OneBotAction';
+import { Static, Type } from '@sinclair/typebox';
+import { NetworkAdapterConfig } from '@/snowcat-onebot/config/config';
+import { StreamPacket, StreamStatus } from './StreamBasic';
+
+export const TestDownloadStreamPayloadSchema = Type.Object({
+  error: Type.Optional(Type.Boolean({ default: false, description: '是否触发测试错误' })),
+});
+
+export type TestDownloadStreamPayload = Static<typeof TestDownloadStreamPayloadSchema>;
+
+export class TestDownloadStream extends OneBotAction<TestDownloadStreamPayload, StreamPacket<{ data: string; }>> {
+  override actionName = ActionName.TestDownloadStream;
+  override actionSummary = '测试下载流';
+  override actionTags = ['流式传输扩展'];
+  override payloadExample = {
+    url: 'http://example.com/file',
+  };
+
+  override returnExample = {
+    success: true,
+  };
+
+  override payloadSchema = TestDownloadStreamPayloadSchema;
+  override returnSchema = Type.Any({ description: '测试流数据' });
+  override useStream = true;
+
+  async _handle (_payload: TestDownloadStreamPayload, _adaptername: string, _config: NetworkAdapterConfig, req: OneBotRequestToolkit) {
+    for (let i = 0; i < 10; i++) {
+      await req.send({ type: StreamStatus.Stream, data: `Index-> ${i + 1}`, data_type: 'data_chunk' });
+      await new Promise(resolve => setTimeout(resolve, 100));
+    }
+    if (_payload.error) {
+      throw new Error('This is a test error');
+    }
+    return {
+      type: StreamStatus.Response,
+      data_type: 'data_complete',
+      data: 'Stream transmission complete',
+    };
+  }
+}