fix: pass Heading component to MDXRemote to fix compilation errors

app/[locale]/[slug]/page.tsx

@@ -49,6 +49,7 @@ const mdxComponents = {
   JsonLd,
   Button,
   Badge,
+  Heading,
   AnimatedCounter,
   GrowthChart,
   DeepDrillAnimation,

app/[locale]/referenzen/page.tsx

@@ -39,6 +39,7 @@ const mdxComponents = {
   ul: (props: any) => <ul className="grid grid-cols-1 gap-2 mb-6" {...props} />,
   li: CustomLi,
   p: (props: any) => <p className="text-neutral-600 text-sm mb-4 leading-relaxed" {...props} />,
+  Heading,
 };
 
 interface PageProps {