新增 iframe 结果接口与圆桌 Step3 结果绘制

- 公开 API：GET /api/public/embed/sessions/{sessionId}/result 返回 messages、generated_text、generated_files
- 圆桌 Step3：内置 roundtable-report 智能体、report/init 与结果绘制 UI

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend-web/src/roundtable-planning/components/Step3Panel.tsx

@@ -8,7 +8,9 @@
  * 拉取 / 文本类预览 / window.open 下载 / 「重新起草」按钮等。
  */
 import { HighFidelityReport } from "@/roundtable-planning/components/HighFidelityReport";
+import type { ModelOption } from "@/roundtable-planning/components/Step3ReportMode";
 import type { Step2Dialogue } from "@/roundtable-planning/hooks/useStep2Orchestration";
+import type { ReportIntent } from "@/roundtable-planning/hooks/useStep3Report";
 import type { ThreadIdMap } from "@/roundtable-planning/api/multi-agent";
 
 export interface Step3PanelProps {
@@ -21,6 +23,13 @@ export interface Step3PanelProps {
     string,
     { speakerId: number; avatarType: string; displayName: string }
   >;
+  /** Step 1 结构化意图 + 当前模型 —— 透传给「结果绘制」的方案可视化智能体。 */
+  intentReady: ReportIntent | null;
+  selectedModel: string;
+  /** 可选模型列表 + 加载态 + 切换器 —— 透传给「结果绘制」的模型选择。 */
+  availableModels: ReadonlyArray<ModelOption>;
+  modelsLoading: boolean;
+  setSelectedModel: (model: string) => void;
   onReset: () => void;
 }
 
@@ -32,6 +41,11 @@ export function Step3Panel(props: Step3PanelProps) {
     hasConsensus,
     step2RoundtableDialogues,
     agentNameToRole,
+    intentReady,
+    selectedModel,
+    availableModels,
+    modelsLoading,
+    setSelectedModel,
     onReset,
   } = props;
 
@@ -55,6 +69,11 @@ export function Step3Panel(props: Step3PanelProps) {
       hasConsensus={hasConsensus}
       seatDeliveries={seatDeliveries}
       seatNameMap={seatNameMap}
+      intentReady={intentReady}
+      selectedModel={selectedModel}
+      availableModels={availableModels}
+      modelsLoading={modelsLoading}
+      setSelectedModel={setSelectedModel}
       onReset={onReset}
     />
   );