Use real Figma assets for 404 page, subtle icon zoom instead of color

- Replace both placeholder images with the actual exports pulled from
  the built Figma page-404 (node 4692:341, file jCCZyh1DGwdjpv1wGge9To):
  testimonial-photo (4699:372) at full 810x306 resolution, and the
  sticky-note-404 (4693:382) — a real photographed/rendered note, not the
  hand-coded CSS+Caveat approximation this had before.
- Help-link icon hover: subtle scale-110 zoom (matching Testimonials.tsx's
  avatar hover) instead of a color inversion.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/not-found.tsx

@@ -110,39 +110,17 @@ export default function NotFound() {
             </Link>
           </Reveal>
 
-          {/* Sticky note — drawn natively (rotated card + tape + Caveat
-              handwriting) rather than a cropped photo asset, since there's
-              no such image in /public and this reads just as well as a
-              coded illustration built from the same tokens (Lora for the
-              "404", Caveat for the handwritten line) the rest of the site
-              already uses for handwritten-style accents (see About.tsx's
-              signature quote). */}
+          {/* Sticky note — real asset exported straight from the built
+              Figma page (page-404, node 4693:382), not a hand-coded
+              approximation — matches project convention of using the
+              actual photographed/rendered note rather than recreating its
+              handwriting in CSS. */}
           <Reveal delay={0.15} className="w-full lg:flex-1 flex items-center justify-center">
-            <div className="relative w-full max-w-[22rem] aspect-square rotate-2 hover:rotate-0 rounded-sm bg-[#EDE3D0] shadow-modal p-8 flex flex-col items-center text-center transition-transform duration-300">
-              <div className="absolute -top-3 left-1/2 -translate-x-1/2 -rotate-3 w-16 h-6 bg-[#d8cdb8]/80" />
-              <p
-                className="font-bold text-text-primary text-[4.5rem] leading-none mt-6"
-                style={{ fontFamily: "var(--font-lora)" }}
-              >
-                404
-              </p>
-              <div className="h-[0.1875rem] w-24 bg-brand mt-3 mb-4" />
-              <p
-                className="text-text-primary text-[1.75rem] leading-[1.15]"
-                style={{ fontFamily: "var(--font-caveat)" }}
-              >
-                Nicht hier.
-                <br />
-                Aber dein Ziel ist
-                <br />
-                sicher nicht weit.
-              </p>
-              <svg viewBox="0 0 32 32" className="size-8 mt-4 text-text-primary" fill="none" aria-hidden="true">
-                <circle cx="11" cy="13" r="1.6" fill="currentColor" />
-                <circle cx="21" cy="13" r="1.6" fill="currentColor" />
-                <path d="M9 19c1.8 2.4 4.4 3.6 7 3.6s5.2-1.2 7-3.6" stroke="currentColor" strokeWidth="1.6" strokeLinecap="round" />
-              </svg>
-            </div>
+            <img
+              alt="Sticky Note: 404. Nicht hier. Aber dein Ziel ist sicher nicht weit."
+              src="/404-sticky-note.png"
+              className="w-full max-w-[22rem] rotate-2 hover:rotate-0 transition-transform duration-300"
+            />
           </Reveal>
         </div>
 
@@ -164,7 +142,7 @@ export default function NotFound() {
                 key={link.href}
                 className="group flex flex-col items-center text-center gap-3 pt-10 md:pt-0 first:pt-0 px-4 transition-transform duration-200 hover:-translate-y-1"
               >
-                <div className="flex size-14 items-center justify-center rounded-full bg-bg-muted text-brand transition-colors duration-200 group-hover:bg-brand group-hover:text-text-primary">
+                <div className="flex size-14 items-center justify-center rounded-full bg-bg-muted text-brand transition-transform duration-300 group-hover:scale-110">
                   {link.icon}
                 </div>
                 <p className="font-semibold text-body text-text-primary">{link.title}</p>