refactor(pro-dialog): remove dead carousel hover-zone styles

Companion to phcode-dev/phoenix-pro@5d61942. The .carousel-hover-zone
rules no longer match any DOM — the hover-reveal flow was replaced by
always-visible arrows.

Author: devvaannsh

src/styles/phoenix-pro.less

@@ -162,18 +162,6 @@
     z-index: 1;
   }
 
-  /* ---- Edge hover zones: only these reveal arrows on hover ---- */
-  .carousel-hover-zone {
-    position: absolute;
-    top: 0;
-    bottom: 0;
-    width: 25%;
-    z-index: 2;
-  }
-
-  .carousel-hover-zone-left { left: 0; }
-  .carousel-hover-zone-right { right: 0; }
-
   .carousel-arrow {
     position: absolute;
     top: 50%;