feat(client): 翻訳をIndexedDBに保存・プッシュ通知を翻訳 (#6396)

* wip

* tabun ok

* better msg

* oops

* fix lint

* Update gulpfile.ts

Co-authored-by: Acid Chicken (硫酸鶏) <root@acid-chicken.com>

* Update src/client/scripts/set-i18n-contexts.ts

Co-authored-by: Acid Chicken (硫酸鶏) <root@acid-chicken.com>

* refactor

Co-authored-by: acid-chicken <root@acid-chicken.com>

* ✨

* wip

* fix lint

* たぶんおk

* fix flush

* Translate Notification

* remove console.log

* fix

* add notifications

* remove san

* wip

* ok

* ✌️

* Update src/prelude/array.ts

Co-authored-by: Acid Chicken (硫酸鶏) <root@acid-chicken.com>

* wip

* i18n refactor

* Update init.ts

* ✌️

Co-authored-by: Acid Chicken (硫酸鶏) <root@acid-chicken.com>
Co-authored-by: syuilo <syuilotan@yahoo.co.jp>

src/client/pages/preferences/index.vue

@@ -99,8 +99,8 @@ import MkRadio from '../../components/ui/radio.vue';
 import MkRange from '../../components/ui/range.vue';
 import XTheme from './theme.vue';
 import XSidebar from './sidebar.vue';
-import i18n from '../../i18n';
 import { langs } from '../../config';
+import { clientDb, set } from '../../db';
 
 const sounds = [
 	null,
@@ -120,8 +120,6 @@ const sounds = [
 ];
 
 export default Vue.extend({
-	i18n,
-
 	metaInfo() {
 		return {
 			title: this.$t('settings') as string
@@ -228,9 +226,23 @@ export default Vue.extend({
 
 	watch: {
 		lang() {
+			const dialog = this.$root.dialog({
+				type: 'waiting',
+				iconOnly: true
+			});
+
 			localStorage.setItem('lang', this.lang);
-			localStorage.removeItem('locale');
-			location.reload();
+
+			return set('_version_', `changeLang-${(new Date()).toJSON()}`, clientDb.i18n)
+				.then(() => location.reload())
+				.catch(() => {
+					dialog.close();
+					this.$root.dialog({
+						type: 'error',
+						iconOnly: true,
+						autoClose: true
+					});
+				});
 		},
 
 		fontSize() {