feat(brand): AirCard-IOS – neues Logo und Name

- Name AirCard-IOS in Kopfzeile, Titel, Meta-Angaben (theme-color,
  apple-mobile-web-app-title) und README
- Website-Icon: neues Logo als favicon.svg, favicon-32.png und deckendes
  apple-touch-icon.png (180 x 180, ohne Rundung)
- Kopfzeile zeigt das Logo (28 px, auf schmalen Schirmen 24 px) vor dem Namen
- Karten-Marken neu aus dem Logo abgeleitet (einfarbig, currentColor):
  Symbol mit drei gestaffelten Karten und ausgeschnittenen Wellen,
  Text als Pfade (Nunito Sans 800); IDs unverändert
- Tests: Labels, Marken-Aufbau, Favicon, Icon-Dateien, index.html

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

web/public/favicon.svg

@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 64 64"><rect width="64" height="64" rx="14" fill="#0F1828"/><g transform="translate(32 32) scale(0.227) translate(-88.655 -32.28)"><path fill="#E8EEF7" fill-rule="evenodd" d="m25.432-5.406 105.64-22.454a26 26 0 0 1 30.837 20.026l9.98 46.951a26 26 0 0 1-20.026 30.838L46.223 92.409a26 26 0 0 1-30.838-20.026l-9.98-46.951A26 26 0 0 1 25.433-5.406m9.318 24.6 39.126-8.316a6 6 0 0 1 2.495 11.738l-39.126 8.316a6 6 0 0 1-2.495-11.738m4.99 23.476 19.563-4.158a6 6 0 0 1 2.495 11.738l-19.563 4.158A6 6 0 0 1 39.74 42.67"/></g></svg>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1024 1024"><defs><linearGradient id="d1" x1="0" x2="1" y1="0" y2="1"><stop offset="0" stop-color="#2e1e8c"/><stop offset="1" stop-color="#4b2fd6"/></linearGradient><linearGradient id="d2" x1="0" x2="1" y1="0" y2="1"><stop offset="0" stop-color="#5b3bf0"/><stop offset="1" stop-color="#8b6cff"/></linearGradient><linearGradient id="d3" x1="0" x2="1" y1="0" y2="1"><stop offset="0" stop-color="#c4b5ff"/><stop offset=".5" stop-color="#8b6cff"/><stop offset="1" stop-color="#4a2bea"/></linearGradient><linearGradient id="sheen" x1="0" x2="0" y1="0" y2="1"><stop offset="0" stop-color="#fff" stop-opacity=".25"/><stop offset=".5" stop-color="#fff" stop-opacity="0"/></linearGradient><radialGradient id="glow" cx="512" cy="780" r="600" gradientUnits="userSpaceOnUse"><stop offset="0" stop-color="#6b4df5" stop-opacity=".65"/><stop offset="1" stop-color="#6b4df5" stop-opacity="0"/></radialGradient><clipPath id="sq"><rect width="1024" height="1024" rx="232"/></clipPath></defs><rect width="1024" height="1024" fill="#0e0a24" rx="232"/><g clip-path="url(#sq)"><path fill="url(#glow)" d="M0 0h1024v1024H0z"/><rect width="680" height="430" x="172" y="360" fill="url(#d1)" rx="80"/><rect width="680" height="430" x="172" y="360" fill="url(#sheen)" rx="80"/><rect width="680" height="430" x="172" y="510" fill="url(#d2)" rx="80"/><rect width="680" height="430" x="172" y="510" fill="url(#sheen)" rx="80"/><rect width="680" height="430" x="172" y="660" fill="url(#d3)" rx="80"/><rect width="680" height="430" x="172" y="660" fill="url(#sheen)" rx="80"/><g fill="none" stroke="#fff" stroke-linecap="round" stroke-width="32"><path d="M591.1 768.9a44 44 0 0 1 0 62.2m34-96.2a92 92 0 0 1 0 130.2"/><path d="M659 701a140 140 0 0 1 0 198"/></g></g></svg>