feat(web): migrate application shell to TanStack Start

- replace the legacy client-only Vite bootstrap with TanStack Router routes, Start SSR, and Nitro output

- compose the reusable layout, navigation, appearance, chats, and notifications blocks with application-owned data

- persist UI preferences through server functions and initialize theme, sidebar, and breakpoint state before hydration

- add React Query, hotkey, toaster, and responsive dashboard integration

- add application-owned Lingui configuration and catalogs, mount the runtime provider, and lazily enable I18nDevtool in development

- remove superseded HTML, main entry, theme provider, and application ESLint configuration

apps/web/src/pages/dashboard-page.tsx

@@ -0,0 +1,48 @@
+import { Button } from "@workspace/ui/components/button"
+import { Slider } from "@workspace/ui/components/slider"
+import { Switch } from "@workspace/ui/components/switch"
+
+export function DashboardPage() {
+  return (
+    <>
+      <img
+        className="h-auto w-full"
+        src="https://pub-c5e31b5cdafb419fb247a8ac2e78df7a.r2.dev/public/assets/background/background-3-blur.webp"
+      />
+      <div className="flex max-w-md min-w-0 flex-col gap-4 text-sm leading-loose">
+        <div>
+          <h1 className="font-medium">Project ready!</h1>
+          <p>You may now add components and start building.</p>
+          <p>We&apos;ve already added the button component for you.</p>
+          <Button variant="ghost" className="mt-2">
+            Button
+          </Button>
+        </div>
+        <div>
+          <Switch />
+          <Slider
+            defaultValue={[75]}
+            max={100}
+            step={1}
+            className="mx-auto w-full max-w-xs"
+          />
+        </div>
+        <div className="font-mono text-xs text-muted-foreground">
+          (Press <kbd>Mod+D</kbd> to toggle dark mode)
+        </div>
+
+        <div>
+          <span className="mr-2">breakpoint:</span>
+          <span className="hidden mobile:inline">mobile</span>
+          <span className="hidden tablet:inline">tablet</span>
+          <span className="hidden desktop:inline">desktop</span>
+        </div>
+        <div>
+          <span className="mr-2">collapsed:</span>
+          <span className="hidden collapsed:inline">true</span>
+          <span className="inline collapsed:hidden">false</span>
+        </div>
+      </div>
+    </>
+  )
+}