Fix select dropdown option colors in page-selector component (#456)

* Initial plan

* Fix select dropdown option styling for better contrast

Co-authored-by: cubap <1119165+cubap@users.noreply.github.com>

* Use browser-native selection styling for better compatibility

Co-authored-by: cubap <1119165+cubap@users.noreply.github.com>

* Use CSS system colors for better accessibility and theme compatibility

Co-authored-by: cubap <1119165+cubap@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: cubap <1119165+cubap@users.noreply.github.com>

Author: Copilot

components/page-selector/index.js

@@ -120,6 +120,10 @@ export default class PageSelector extends HTMLElement {
                     font-family: inherit;
                     cursor: pointer;
                 }
+                select option {
+                    background-color: Canvas;
+                    color: CanvasText;
+                }
             </style>
             <select part="select" aria-label="Select page">
                 ${optionsHtml}