fix(sidebar): honor prefers-reduced-motion on the panel transition

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

Author: frankieyan

src/sidebar/sidebar.module.css

@@ -162,6 +162,6 @@
     .panel,
     .backdrop,
     .resizeHandle {
-        transition: none;
+        transition: none !important;
     }
 }