Alerts M3 per while

Restyles alerts.in.ua in Material 3 Expressive and adds an "Alerts M3" tab to the site's settings. Pick your regions to see their alert status on the map, get desktop notifications and a sound when an alert starts or ends, and see 🔴 in the tab title. Also: custom accent color, map colors that follow the accent, adjustable corner roundness, draggable floating panels, and keyboard shortcuts. The interface language follows the site's language (Ukrainian or English).