feat: 统一 AI 设计 Workspace 与生成任务链路

需求：以设计项目组织固定设计 Agent 对话、方向确认和图片视频任务。

实现：新增 Works Square 云端适配与开发态本地适配，统一 Host API、Quote 确认、任务轮询及私有媒体 Range 代理。

electron/api/route-utils.ts

@@ -25,7 +25,7 @@ export async function parseJsonBody<T>(req: IncomingMessage): Promise<T> {
 }
 
 /**
- * Validate that mutation requests (POST/PUT/DELETE) carry a JSON Content-Type.
+ * Validate that mutation requests (POST/PUT/PATCH/DELETE) carry a JSON Content-Type.
  * This prevents "simple request" CSRF where the browser skips the preflight
  * when Content-Type is text/plain or application/x-www-form-urlencoded.
  */
@@ -51,7 +51,7 @@ export function setCorsHeaders(res: ServerResponse, origin?: string): void {
     res.setHeader('Access-Control-Allow-Origin', origin);
     res.setHeader('Vary', 'Origin');
   }
-  res.setHeader('Access-Control-Allow-Methods', 'GET,POST,PUT,DELETE,OPTIONS');
+  res.setHeader('Access-Control-Allow-Methods', 'GET,POST,PUT,PATCH,DELETE,OPTIONS');
   res.setHeader('Access-Control-Allow-Headers', 'Content-Type, Authorization, X-NianCode-Access-Token');
 }