🐛 fix(vscode): issue/patch 用 null 清空 worktree 字段以便 webview 即时刷新

vscode/src/webhook/coordinator.ts

@@ -1062,7 +1062,8 @@ class WebhookCoordinator {
         this.activePanel.postMessage({
           type: 'issue/patch',
           issueNumber: event.issueNumber,
-          patch: { pr: undefined },
+          // null 才能过 postMessage；undefined 会被序列化丢掉
+          patch: { pr: null },
         })
       }
       catch (err) {