feat: Migrate hardcoded strings to i18n calls

src/lib/components/chat/ModelSelector.svelte

@@ -12,7 +12,7 @@
 	const saveDefaultModel = async () => {
 		const hasEmptyModel = selectedModels.filter((it) => it === '');
 		if (hasEmptyModel.length) {
-			toast.error('Choose a model before saving...');
+			toast.error($i18n.t('Choose a model before saving...'));
 			return;
 		}
 		settings.set({ ...$settings, models: selectedModels });
@@ -22,7 +22,7 @@
 			console.log('setting default models globally');
 			await setDefaultModels(localStorage.token, selectedModels.join(','));
 		}
-		toast.success('Default model updated');
+		toast.success($i18n.t('Default model updated'));
 	};
 
 	$: if (selectedModels.length > 0 && $models.length > 0) {