Galerie aller shadcn/ui-Komponenten auf der Startseite

- Alle 63 Komponenten aus dem shadcn-Register installiert (Stil base-luma)
- Galerie unter components/galerie mit 7 Kategorien und Sprungnavigation
- Inhaltsbreite auf max-w-6xl erweitert
- shadcn-Hauptfarbe auf E&P-Tiefblau, größter Radius eckig
- App-Titel "UI-Galerie"

Co-Authored-By: Claude Opus 5.5 <[email protected]>

frontend-starter/components/ui/checkbox.tsx

@@ -0,0 +1,28 @@
+"use client"
+
+import { Checkbox as CheckboxPrimitive } from "@base-ui/react/checkbox"
+import { cn } from "cn"
+import { CheckIcon } from "lucide-react"
+
+function Checkbox({ className, ...props }: CheckboxPrimitive.Root.Props) {
+  return (
+    <CheckboxPrimitive.Root
+      data-slot="checkbox"
+      className={cn(
+        "peer relative flex size-4 shrink-0 items-center justify-center rounded-[5px] border border-transparent bg-input/90 transition-shadow outline-none group-has-disabled/field:opacity-50 group-has-[:focus-visible]/field-label:ring-0 group-has-[:focus-visible]/field-label:not-data-checked:border-transparent after:absolute after:-inset-x-3 after:-inset-y-2 focus-visible:border-ring focus-visible:ring-3 focus-visible:ring-ring/30 disabled:cursor-not-allowed disabled:opacity-50 aria-invalid:border-destructive aria-invalid:ring-3 aria-invalid:ring-destructive/20 aria-invalid:aria-checked:border-primary dark:aria-invalid:border-destructive/50 dark:aria-invalid:ring-destructive/40 data-checked:border-primary data-checked:bg-primary data-checked:text-primary-foreground group-has-[:focus-visible]/field-label:data-checked:border-primary dark:data-checked:bg-primary",
+        className
+      )}
+      {...props}
+    >
+      <CheckboxPrimitive.Indicator
+        data-slot="checkbox-indicator"
+        className="grid place-content-center text-current transition-none [&>svg]:size-3.5"
+      >
+        <CheckIcon
+        />
+      </CheckboxPrimitive.Indicator>
+    </CheckboxPrimitive.Root>
+  )
+}
+
+export { Checkbox }