feat(agent): 添加流式对话API实现

实现基于SSE的流式对话接口，支持消息发送和回调处理
添加@microsoft/fetch-event-source依赖

package.json

@@ -20,6 +20,7 @@
     "prepare": ""
   },
   "dependencies": {
+    "@microsoft/fetch-event-source": "^2.0.1",
     "@unhead/vue": "2.0.19",
     "@vant/touch-emulator": "^1.4.0",
     "@vant/use": "^1.6.0",

pnpm-lock.yaml

@@ -11,6 +11,9 @@ importers:
 
   .:
     dependencies:
+      '@microsoft/fetch-event-source':
+        specifier: ^2.0.1
+        version: 2.0.1
       '@unhead/vue':
         specifier: 2.0.19
         version: 2.0.19(vue@3.5.25(typescript@5.9.3))
@@ -1017,6 +1020,9 @@ packages:
   '@jridgewell/trace-mapping@0.3.31':
     resolution: {integrity: sha512-zzNR+SdQSDJzc8joaeP8QQoCQr8NuYx2dIIytl1QeBEZHJ9uW6hebsrYgbz8hJwUQao3TWCMtmfV8Nu1twOLAw==}
 
+  '@microsoft/fetch-event-source@2.0.1':
+    resolution: {integrity: sha512-W6CLUJ2eBMw3Rec70qrsEW0jOm/3twwJv21mrmj2yORiaVmVYGS4sSS5yUwvQc1ZlDLYGPnClVWmUUMagKNsfA==}
+
   '@noble/hashes@1.8.0':
     resolution: {integrity: sha512-jCs9ldd7NwzpgXDIf6P3+NrHh9/sD6CQdxHyjQI+h/6rDNo88ypBxxz45UDuZHz9r3tNz7N/VInSVoVdtXEI4A==}
     engines: {node: ^14.21.3 || >=16}
@@ -5053,6 +5059,8 @@ snapshots:
       '@jridgewell/resolve-uri': 3.1.2
       '@jridgewell/sourcemap-codec': 1.5.5
 
+  '@microsoft/fetch-event-source@2.0.1': {}
+
   '@noble/hashes@1.8.0': {}
 
   '@paralleldrive/cuid2@2.3.1':

src/api/agent/index.ts

@@ -0,0 +1,98 @@
+const AGENT_BASE_URL = '';
+
+import { fetchEventSource } from '@microsoft/fetch-event-source';
+
+export const baseInfoApi = () => {
+  return fetch(`${AGENT_BASE_URL}`, {
+    method: 'GET',
+  });
+}
+
+/**
+ * 流式对话接口，返回流式 JSON 数据，形如 {"text":"我来"}
+ * @param message 用户消息
+ * @param callbacks 回调函数对象
+ * @param options 可选配置，包含 abort signal
+ * @example
+ * // 使用示例：
+ * streamApi('你好', {
+ *   onopen(response) {
+ *     console.log('连接已建立', response);
+ *   },
+ *   onmessage(data) {
+ *     // data 是服务器发送的原始字符串，如 '{"text":"我来"}'
+ *     console.log('收到消息:', data);
+ *   },
+ *   onclose() {
+ *     console.log('连接已关闭');
+ *   },
+ *   onerror(error) {
+ *     console.error('连接错误:', error);
+ *   }
+ * }, { signal: abortController.signal });
+ */
+export const streamApi = (
+  message: string,
+  callbacks: {
+    onopen?: (response: Response) => void;
+    onmessage?: (data: string) => void;
+    onclose?: () => void;
+    onerror?: (error: Error) => void;
+  },
+  options?: { signal?: AbortSignal }
+) => {
+  // 启动 fetchEventSource
+  fetchEventSource(`${AGENT_BASE_URL}/stream`, {
+    method: 'POST',
+    headers: {
+      'Content-Type': 'application/json',
+    },
+    body: JSON.stringify({ message }),
+    signal: options?.signal,
+    async onopen(response) {
+      // 检查响应是否正常
+      if (response.ok && response.headers.get('content-type')?.includes('text/event-stream')) {
+        // 连接成功，调用 onopen 回调
+        callbacks.onopen?.(response);
+      } else {
+        // 如果响应不正常，抛出错误
+        throw new Error(`SSE 连接失败: ${response.status} ${response.statusText}`);
+      }
+    },
+    onmessage(msg) {
+      // 处理服务器发送的消息
+      // msg.data 应该是 JSON 字符串，如 {"text":"..."}
+      try {
+        const data = msg.data;
+        console.log('Received message:', data);
+        if (data && data !== '[DONE]') {
+          callbacks.onmessage?.(data);
+        }
+      } catch (error) {
+        console.warn('处理 SSE 消息时出错:', error);
+      }
+    },
+    onclose() {
+      // 连接关闭
+      console.log('SSE 连接已关闭');
+      callbacks.onclose?.();
+    },
+    onerror(err) {
+      // 发生错误
+      console.error('SSE 连接错误:', err);
+      callbacks.onerror?.(err instanceof Error ? err : new Error(String(err)));
+
+      // 重新抛出错误以停止重试
+      throw err;
+    },
+  }).catch(error => {
+    // 捕获 fetchEventSource 的 Promise 拒绝
+    if (error.name !== 'AbortError') {
+      console.error('fetchEventSource 错误:', error);
+      callbacks.onerror?.(error instanceof Error ? error : new Error(String(error)));
+    } else {
+      // AbortError 是正常的取消操作，不需要调用 onerror
+      console.log('请求已被取消');
+    }
+  });
+}