remove duplicate "System" in select menu

src/lib/components/chat/Settings/General.svelte

@@ -137,7 +137,6 @@
 						placeholder="Select a theme"
 						on:change="{() => handleThemeChange(selectedTheme)}"
 					>
-      			<option value="system">System</option>
 						<option value="system">⚙️ {$i18n.t('System')}</option>
 						<option value="dark">🌑 {$i18n.t('Dark')}</option>
 						<option value="light">☀️ {$i18n.t('Light')}</option>