Fix hero video: use full 1920x1080, center via object-position

Previous crop distorted aspect ratio. Now uses original 16:9 video
with object-position: 35% 40% to center the light sculpture in the
hero viewport.

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

public/index.html

@@ -115,7 +115,7 @@
             min-height: 100%;
             transform: translate(-50%, -50%);
             object-fit: cover;
-            object-position: center center;
+            object-position: 35% 40%;
             z-index: 0;
         }