重构 Agent 聊天，支持分支管理与消息克隆

src/lib/chatStream.ts

@@ -181,3 +181,52 @@ export const streamAgentChat = async ({
     }
   }
 };
+
+export const abortAgentChat = async (sessionId?: string) => {
+  if (!sessionId) {
+    return;
+  }
+
+  const response = await apiFetch(`${config.AGENT_URL}/api/v1/agent/chat/abort`, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+    },
+    body: JSON.stringify({
+      session_id: sessionId,
+    }),
+    projectHeaderMode: "include",
+    skipAuthRedirect: true,
+  });
+
+  if (!response.ok) {
+    const detail = await response.text();
+    throw new Error(detail || `abort request failed: ${response.status}`);
+  }
+};
+
+export const forkAgentChat = async (sessionId: string | undefined, keepMessageCount: number) => {
+  const response = await apiFetch(`${config.AGENT_URL}/api/v1/agent/chat/fork`, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+    },
+    body: JSON.stringify({
+      session_id: sessionId,
+      keep_message_count: keepMessageCount,
+    }),
+    projectHeaderMode: "include",
+    skipAuthRedirect: true,
+  });
+
+  if (!response.ok) {
+    const detail = await response.text();
+    throw new Error(detail || `fork request failed: ${response.status}`);
+  }
+
+  const payload = (await response.json()) as { session_id?: string };
+  if (!payload.session_id) {
+    throw new Error("fork request returned no session_id");
+  }
+  return payload.session_id;
+};