完成图片编辑器宣发素材生成

新增宣发素材入口、工作流模型、画布生成卡片和参考图选择能力。

接入宣发素材真实生图请求，隐藏 Prompt 摘要和约束预览，并将约束作为内部 Prompt 使用。

支持游戏首图、详情五图、运营海报尺寸，其中详情五图一次生成五张 720x1280 竖图。

后端仅对 publication-material 生图扣 5 泥点，并沿用现有失败退款逻辑。

补充前后端测试和宣发素材设计文档。

src/services/image-editor/editorProjectClient.test.ts

@@ -698,6 +698,49 @@ describe('editorProjectClient', () => {
     );
   });
 
+  it('passes publication material generation kind and size to the backend BFF', async () => {
+    requestJsonMock.mockResolvedValueOnce({
+      imageSrc: 'data:image/png;base64,publication',
+      width: 720,
+      height: 1280,
+      sourceType: 'generated',
+      prompt: '宣发素材 prompt',
+      actualPrompt: '宣发素材 prompt',
+      model: 'gpt-image-2',
+      provider: 'VectorEngine',
+      taskId: 'vector-publication-1',
+    });
+
+    const result = await generateEditorImage({
+      prompt: '宣发素材 prompt',
+      size: '720x1280',
+      kind: 'publication-material',
+      candidateCount: 5,
+      referenceImageSrcs: ['data:image/png;base64,ref'],
+    });
+
+    expect(result.height).toBe(1280);
+    expect(requestJsonMock).toHaveBeenCalledWith(
+      '/api/editor/images/generations',
+      expect.objectContaining({
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({
+          prompt: '宣发素材 prompt',
+          size: '720x1280',
+          kind: 'publication-material',
+          candidateCount: 5,
+          referenceImageSrcs: ['data:image/png;base64,ref'],
+        }),
+      }),
+      '生成图片失败',
+      expect.objectContaining({
+        timeoutMs: 1_200_000,
+        retry: { maxRetries: 0 },
+      }),
+    );
+  });
+
   it('generates editor character animations through the backend BFF', async () => {
     requestJsonMock.mockResolvedValueOnce({
       taskId: 'character-animation-1',