Der Eine.: drop "Warum" section, widen + restyle Focus icons

- Removed the brand-story "Warum Der Eine.?" section entirely — for a
  6,90€ accessory item its one unique fact (the two-sided engraving) was
  already covered by Hero/Focus, the rest was pure narrative that didn't
  aid the buying decision.
- Focus.tsx ("Was kann er?") widened to max-w-[75rem] (the site's
  standard content width, same as Tools.tsx/HowItWorks.tsx) instead of
  the narrower inset borrowed from HowItWorks' 3-item version.
- Icons switched from plain black line icons to a circle-badge + brand
  orange (#f6a701) stroke treatment — matching the icon language already
  used elsewhere on this page (IconCheck) and site (HowItWorks' own
  stroked-circle step icon), the flat black icons read as a mismatched
  style.

app/der-eine/page.tsx

@@ -1,6 +1,5 @@
 import type { Metadata } from "next";
 import { Hero } from "./components/Hero";
-import { Why } from "./components/Why";
 import { Focus } from "./components/Focus";
 import { PasstDazu } from "./components/PasstDazu";
 import { Footer } from "../components/Footer";
@@ -45,7 +44,6 @@ export default async function DerEinePage() {
       <main className="flex flex-col flex-1">
         <Hero />
         <Focus />
-        <Why />
         <PasstDazu />
       </main>
       <Footer />