fix: review fixes (#17208)

* fix: OAuthのContent-Typeを正しく判定するように

* fix(frontend): fix outdated comments

* fix: storagePersistenceのtop-level awaitを解消

* fix

* fix(frontend): add comment

Co-Authored-By: anatawa12 <anatawa12@icloud.com>

* fix

* fix: rename `users/get-following-users-by-birthday`

* fix: fix types

* Update MkForm.vue

* refactor utility/storage.ts

---------

Co-authored-by: anatawa12 <anatawa12@icloud.com>
Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

packages/frontend/src/pages/page-editor/page-editor.blocks.vue

@@ -14,7 +14,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 >
 	<template #default="{ item }">
 		<div>
-			<!-- divが無いとエラーになる https://github.com/SortableJS/vue.draggable.next/issues/189 -->
+			<!-- divが無いとエラーになる -->
 			<component :is="getComponent(item.type) as any" :modelValue="item" @update:modelValue="updateItem" @remove="() => removeItem(item)"/>
 		</div>
 	</template>