fix(ui): kiosk dropdown flash + never inherit the OS light theme

Outside-close listeners move from click to pointerdown: pointerdown
fires before the open-toggle re-render, so the kiosk's slow software
compositing can no longer detach the click target mid-flight and close
the menu the instant it opens. color-scheme:dark (CSS + meta) pins every
native control — select popups, scrollbars, pickers — dark regardless of
the user's OS theme; explicit select/option colors cover Firefox.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

neode-ui/src/style.css

@@ -2,6 +2,22 @@
 @tailwind components;
 @tailwind utilities;
 
+/* The app is dark-only — NEVER let the OS/browser theme leak into native
+   controls. Without this, select popups / scrollbars / date pickers follow
+   the user's OS setting (a light-mode ThinkPad rendered white dropdown
+   lists inside the dark UI, 2026-07-22). color-scheme pins Chromium's
+   native select popup dark; the explicit select/option rules cover
+   Firefox and the closed control itself. */
+:root {
+  color-scheme: dark;
+}
+select,
+select option,
+select optgroup {
+  background-color: #16181d;
+  color: #fff;
+}
+
 /* Montserrat - header font (used in neode present) */
 @font-face {
   font-family: 'Montserrat';