fix nits

Author: sawka

emain/emain-window.ts

@@ -728,7 +728,7 @@ ipcMain.on("set-waveai-open", (event, isOpen: boolean) => {
     }
 });
 
-ipcMain.handle("close-tab", async (event, workspaceId, tabId, confirmClose) => {
+ipcMain.handle("close-tab", async (event, workspaceId: string, tabId: string, confirmClose: boolean) => {
     const ww = getWaveWindowByWorkspaceId(workspaceId);
     if (ww == null) {
         console.log(`close-tab: no window found for workspace ws=${workspaceId} tab=${tabId}`);

frontend/app/tab/tabbar.tsx

@@ -597,7 +597,7 @@ const TabBar = memo(({ workspace }: TabBarProps) => {
             .closeTab(ws.oid, tabId, confirmClose)
             .then((didClose) => {
                 if (didClose) {
-                    tabsWrapperRef.current.style.setProperty("--tabs-wrapper-transition", "width 0.3s ease");
+                    tabsWrapperRef.current?.style.setProperty("--tabs-wrapper-transition", "width 0.3s ease");
                     deleteLayoutModelForTab(tabId);
                 }
             })