Integrate backend APIs and move review to center editor tab

src/core/ChatClientApi.js

@@ -0,0 +1,45 @@
+import { ApiHttpClient } from "./ApiHttpClient.js";
+
+export class ChatClientApi {
+  constructor(http = new ApiHttpClient(), pollMs = 700, timeoutMs = 120000) {
+    this.http = http;
+    this.pollMs = pollMs;
+    this.timeoutMs = timeoutMs;
+  }
+
+  async createDialog(ragSessionId) {
+    const response = await this.http.request("/api/chat/dialogs", {
+      method: "POST",
+      body: JSON.stringify({ rag_session_id: ragSessionId })
+    });
+    return response.dialog_session_id;
+  }
+
+  async sendMessage(payload) {
+    const queued = await this.http.request("/api/chat/messages", {
+      method: "POST",
+      body: JSON.stringify({
+        dialog_session_id: payload.dialog_session_id,
+        rag_session_id: payload.rag_session_id,
+        message: payload.message,
+        attachments: payload.attachments || []
+      })
+    });
+
+    const taskId = queued.task_id;
+    const started = Date.now();
+    while (Date.now() - started < this.timeoutMs) {
+      const status = await this.http.request(`/api/tasks/${encodeURIComponent(taskId)}`);
+      if (status.status === "done") return status;
+      if (status.status === "error") {
+        throw new Error(status.error?.desc || "Task failed");
+      }
+      await this.#sleep(this.pollMs);
+    }
+    throw new Error("Task polling timeout");
+  }
+
+  #sleep(ms) {
+    return new Promise((resolve) => setTimeout(resolve, ms));
+  }
+}