Merge feature/gerbil-icon-redesign: GerbilIcon SVG neu gezeichnet

Julian fand die alte Silhouette bescheiden. Neue Rennmaus-Silhouette
(sitzende Pose, layered ears, Pfoten, geschwungener Schwanz + Tuft).
Komponenten-API unveraendert (Props/viewBox/role/aria-label/style) ->
Consumer + e2e Selektoren intakt. QA: tsc+vite build green, vitest 122/122.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

gerbil-manager-web/src/components/GerbilIcon.tsx

@@ -21,15 +21,17 @@ export default function GerbilIcon({ size = '1em', style, className }: Props) {
       aria-label="Rennmaus"
     >
       {/* body — sitting upright */}
-      <path d="M40 14c6 0 11 5 11 12 0 4-2 7-2 11 0 10-6 16-15 16-8 0-14-6-14-15 0-13 9-24 20-24z" />
-      {/* ear */}
-      <circle cx="46" cy="15" r="5" />
-      {/* hind paw */}
-      <ellipse cx="24" cy="52" rx="9" ry="3.5" />
-      {/* long curved tail with tuft */}
-      <path d="M16 51c-7 1-13-2-15-9-1-4 0-8 3-10 1 3 1 6 3 8 3 3 7 4 11 4z" />
+      <path d="M 34 23 C 38 20, 44 21, 46 25 C 47 27, 45 30, 41 31 C 38 32, 40 38, 40 42 C 40 48, 36 51, 31 52 C 25 52, 21 47, 21 40 C 21 31, 27 25, 34 23 Z" />
+      {/* ears */}
+      <path d="M 36 22 Q 33 13 39 11 Q 42 13 39 21 Z" />
+      <path d="M 32 23 Q 30 15 35 13 Q 37 15 35 22 Z" opacity="0.6" />
       {/* front paw */}
-      <path d="M30 45c3 0 5 1 5 4-3 1-6 1-7-2 0-1 1-2 2-2z" />
+      <path d="M 41 33 Q 46 33 46 36 Q 44 38 41 35 Z" />
+      {/* hind paw */}
+      <path d="M 21 49 C 19 53, 23 55, 30 55 C 33 55, 34 52, 30 50 Z" />
+      {/* tail and tuft */}
+      <path d="M 21 47 C 14 51, 9 46, 8 41 C 7 35, 11 27, 16 22 C 17 21, 18 22, 17 23 C 13 28, 10 35, 11 40 C 12 44, 15 47, 21 44 Z" />
+      <path d="M 16 22 C 16 16, 13 11, 16 7 C 20 3, 22 10, 19 16 C 18 19, 17 21, 16 22 Z" />
     </svg>
   )
 }