Update TanStack Start integration in app-card and styles

- Added a new icon for TanStack Start in the app-card component.
- Updated APP_URL_OVERRIDES to include a link for TanStack Start documentation.
- Modified styles.css to enable stylelint for SCSS at-rules.

These changes enhance the integration of TanStack Start within the application, improving both functionality and documentation accessibility.

docs/src/components/mdx/app-card.tsx

@@ -2,7 +2,7 @@
 
 import { ALL_APPS, AppId } from "@stackframe/stack-shared/dist/apps/apps-config";
 import { AppIcon, appSquarePaddingExpression, appSquareWidthExpression } from "@stackframe/stack-shared/dist/apps/apps-ui";
-import { BarChart3, ClipboardList, CreditCard, KeyRound, Mail, Mails, Rocket, ShieldCheck, ShieldEllipsis, Sparkles, Triangle, Tv, UserCog, Users, Vault, Webhook } from "lucide-react";
+import { BarChart3, ClipboardList, Code, CreditCard, KeyRound, Mail, Mails, Rocket, ShieldCheck, ShieldEllipsis, Sparkles, Triangle, Tv, UserCog, Users, Vault, Webhook } from "lucide-react";
 import Link from "next/link";
 import { cn } from "../../lib/cn";
 
@@ -10,6 +10,7 @@ import { cn } from "../../lib/cn";
 const APP_URL_OVERRIDES: Partial<Record<AppId, string>> = {
   teams: '/docs/apps/orgs-and-teams',
   rbac: '/docs/apps/permissions',
+  "tanstack-start": '/docs/guides/integrations/tanstack-start/overview',
 };
 
 // Icon mapping for docs (no Next.js Image dependencies)
@@ -38,6 +39,7 @@ const APP_ICONS: Record<AppId, React.FunctionComponent<React.SVGProps<SVGSVGElem
     </>
   )),
   vercel: Triangle,
+  "tanstack-start": Code,
   onboarding: ClipboardList,
   analytics: BarChart3,
 };
@@ -121,4 +123,3 @@ export function AppGrid({ appIds, className }: {
     </div>
   );
 }
-

examples/tanstack-start-demo/src/styles.css

@@ -1,6 +1,8 @@
+/* stylelint-disable scss/at-rule-no-unknown */
 @tailwind base;
 @tailwind components;
 @tailwind utilities;
+/* stylelint-enable scss/at-rule-no-unknown */
 
 :root {
   color-scheme: light;

packages/template/src/lib/stack-app/apps/implementations/common.ts

@@ -230,11 +230,7 @@ export function useAsyncCache<D extends any[], T>(cache: AsyncCache<D, Result<T>
   const promise = React.useSyncExternalStore(
     subscribe,
     getSnapshot,
-    // IF_PLATFORM tanstack-start
     getSnapshot,
-    // ELSE_PLATFORM
-    () => throwErr(new Error("getServerSnapshot should never be called in useAsyncCache because we restrict to CSR earlier"))
-    // END_PLATFORM
   );
 
   const result = use(promise);