fix(stack): reemplazar ícono OpenAI falso por logomark oficial SVG

El crosshair era un ícono genérico. Ahora usa el path oficial
del logomark de OpenAI (figura geométrica entrelazada, viewBox 0 0 41 41).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: devsart95

src/components/sections/Stack.tsx

@@ -35,11 +35,8 @@ const TECHS: Tech[] = [
   { label: 'Terraform',  color: '#7b42bc', icon: <SI path={siTerraform.path}  color="#7b42bc" /> },
   { label: 'Anthropic',  color: '#d97706', icon: <SI path={siAnthropic.path}  color="#d97706" /> },
   { label: 'OpenAI',     color: '#10a37f', icon: (
-    <svg viewBox="0 0 28 28" fill="none">
-      <path d="M14 4a10 10 0 1 1 0 20A10 10 0 0 1 14 4z" stroke="#10a37f" strokeWidth="1.2" fill="none"/>
-      <path d="M14 4 Q22 9 22 14 Q22 19 14 24 Q6 19 6 14 Q6 9 14 4z" stroke="#10a37f" strokeWidth="1" fill="none" opacity=".5"/>
-      <path d="M6 14h16M14 4v20" stroke="#10a37f" strokeWidth="1" opacity=".4"/>
-      <circle cx="14" cy="14" r="3" stroke="#10a37f" strokeWidth="1.3" fill="none"/>
+    <svg viewBox="0 0 41 41" fill="#10a37f" aria-hidden="true">
+      <path d="M37.532 16.87a9.963 9.963 0 00-.856-4.761 10.107 10.107 0 00-9.269-6.1 9.99 9.99 0 00-7.516 3.41 9.974 9.974 0 00-8.962 5.548 10.089 10.089 0 001.261 11.77 9.95 9.95 0 00.856 4.762 10.106 10.106 0 009.268 6.099 9.984 9.984 0 007.517-3.41 9.976 9.976 0 008.962-5.547 10.086 10.086 0 00-1.261-11.77zm-20.18 12.902a7.416 7.416 0 01-4.738-1.682.93.93 0 00.048-.028l7.867-4.57a1.289 1.289 0 00.647-1.12V13.83l3.324 1.924a.12.12 0 01.065.09v9.245a7.465 7.465 0 01-7.213 7.683zM5.135 23.44a7.436 7.436 0 01-.883-4.998 9.822 9.822 0 00.235.14l7.867 4.57a1.29 1.29 0 001.294 0l9.602-5.58v3.849a.12.12 0 01-.046.097l-7.951 4.614a7.461 7.461 0 01-10.118-2.692zM3.24 13.094a7.453 7.453 0 013.843-3.276v9.392a1.29 1.29 0 00.647 1.12l9.567 5.558-3.324 1.924a.12.12 0 01-.113.01L5.19 22.808A7.462 7.462 0 013.24 13.094zm27.416 6.41l-9.601-5.579 3.323-1.924a.12.12 0 01.113-.011l8.671 5.015a7.458 7.458 0 01-1.155 13.452V21.11a1.288 1.288 0 00-.351-.606zm3.309-5.046a9.85 9.85 0 00-.235-.14l-7.866-4.57a1.29 1.29 0 00-1.295 0L14.97 15.33v-3.849a.12.12 0 01.047-.097l7.95-4.609a7.458 7.458 0 0110.997 7.733zm-20.761 6.83l-3.324-1.924a.12.12 0 01-.065-.09v-9.246a7.459 7.459 0 0112.23-5.741.93.93 0 00-.048.029l-7.868 4.57a1.289 1.289 0 00-.646 1.12l-.279 11.282zm1.804-3.907l4.273-2.479 4.274 2.473v4.946l-4.274 2.473-4.273-2.473V17.38z"/>
     </svg>
   )},
   { label: 'Linux / VPS', color: '#fcc624', icon: <SI path={siLinux.path}    color="#fcc624" /> },