add system theme ⚙️ option to select menu

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

@@ -138,6 +138,7 @@
 						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">☀️ {$i18n.t('Light')}</option>
 						<option value="rose-pine dark">🪻 {$i18n.t('Rosé Pine')}</option>