enhance(client): Sync widgets (#8512)

* feature: sync widgets among devices

* fix

* nanka iroiro
* classic.widgets.vueの機能をuniversal.widgets.vueに統合
* 左右のウィジェット編集状態を同期するように
* 左右やカラム間でウィジェットを行き来できるように
* MkWidgetsをCSS Module化

* set min-height: 100px;

* fix deck widget

* Update packages/client/src/ui/deck/widgets-column.vue

Co-authored-by: syuilo <Syuilotan@yahoo.co.jp>

* merge

* Update classic.vue

* Delete classic.widgets.vue

Co-authored-by: syuilo <Syuilotan@yahoo.co.jp>

packages/frontend/src/ui/deck/widgets-column.vue

@@ -4,7 +4,7 @@
 
 	<div class="wtdtxvec">
 		<div v-if="!(column.widgets && column.widgets.length > 0) && !edit" class="intro">{{ i18n.ts._deck.widgetsIntroduction }}</div>
-		<XWidgets :edit="edit" :widgets="column.widgets" @add-widget="addWidget" @remove-widget="removeWidget" @update-widget="updateWidget" @update-widgets="updateWidgets" @exit="edit = false"/>
+		<XWidgets :edit="edit" :widgets="column.widgets ?? []" @add-widget="addWidget" @remove-widget="removeWidget" @update-widget="updateWidget" @update-widgets="updateWidgets" @exit="edit = false"/>
 	</div>
 </XColumn>
 </template>