feat: turbostarter boilerplate

Production-ready Next.js boilerplate with:
- Runtime env validation (fail-fast on missing vars)
- Feature-gated config (S3, Stripe, email, OAuth)
- Docker + Coolify deployment pipeline
- PostgreSQL + pgvector, MinIO S3, Better Auth
- TypeScript strict mode (no ignoreBuildErrors)
- i18n (en/es), AI modules, billing, monitoring

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/ui/mobile/src/components/checkbox.tsx

@@ -0,0 +1,48 @@
+import * as CheckboxPrimitive from "@rn-primitives/checkbox";
+
+import { cn } from "@turbostarter/ui";
+
+import { Icons } from "./icons";
+
+const DEFAULT_HIT_SLOP = 24;
+
+function Checkbox({
+  className,
+  checkedClassName,
+  indicatorClassName,
+  iconClassName,
+  ...props
+}: CheckboxPrimitive.RootProps &
+  React.RefAttributes<CheckboxPrimitive.RootRef> & {
+    checkedClassName?: string;
+    indicatorClassName?: string;
+    iconClassName?: string;
+  }) {
+  return (
+    <CheckboxPrimitive.Root
+      className={cn(
+        "border-input dark:bg-input/30 size-4 shrink-0 overflow-hidden rounded-[4px] border shadow-sm shadow-black/5",
+        props.checked && cn("border-primary", checkedClassName),
+        props.disabled && "opacity-50",
+        className,
+      )}
+      hitSlop={DEFAULT_HIT_SLOP}
+      {...props}
+    >
+      <CheckboxPrimitive.Indicator
+        className={cn(
+          "bg-primary h-full w-full items-center justify-center",
+          indicatorClassName,
+        )}
+      >
+        <Icons.Check
+          size={12}
+          strokeWidth={3.5}
+          className={cn("text-primary-foreground", iconClassName)}
+        />
+      </CheckboxPrimitive.Indicator>
+    </CheckboxPrimitive.Root>
+  );
+}
+
+export { Checkbox };