refactor: extract signals filter builder, add ESLint 10 config, fix low-hanging issues

web/components/ChartCard/DividerCard.tsx

@@ -13,12 +13,14 @@ export default function DividerCard({ title, onEdit, onDelete }: Props) {
       <div className="flex-1 h-px bg-gray-600" />
       <div className="flex gap-1 shrink-0">
         <button
+          aria-label="Edit divider"
           onClick={onEdit}
           className="text-xs text-gray-500 hover:text-white px-1.5 py-0.5 rounded hover:bg-gray-700"
         >
           ✏️
         </button>
         <button
+          aria-label="Delete divider"
           onClick={onDelete}
           className="text-xs text-gray-500 hover:text-red-400 px-1.5 py-0.5 rounded hover:bg-gray-700"
         >