feat: initial commit — asaas-checkout template white-label

Template genérico de checkout com ASAAS, parametrizado via env vars.
Inclui fluxo completo: checkout → pedido → polling → webhook → admin.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/ui/separator.tsx

@@ -0,0 +1,14 @@
+"use client"
+import * as React from "react"
+import * as SeparatorPrimitive from "@radix-ui/react-separator"
+import { cn } from "@/lib/utils"
+const Separator = React.forwardRef<
+  React.ElementRef<typeof SeparatorPrimitive.Root>,
+  React.ComponentPropsWithoutRef<typeof SeparatorPrimitive.Root>
+>(({ className, orientation = "horizontal", decorative = true, ...props }, ref) => (
+  <SeparatorPrimitive.Root ref={ref} decorative={decorative} orientation={orientation}
+    className={cn("shrink-0 bg-border", orientation === "horizontal" ? "h-[1px] w-full" : "h-full w-[1px]", className)}
+    {...props} />
+))
+Separator.displayName = SeparatorPrimitive.Root.displayName
+export { Separator }