chore: 著作権とライセンスについての情報を各ファイルに追加する (#11348)

* chore: Add the SPDX information to each file

Add copyright and licensing information as defined in version 3.0 of
the REUSE Specification.

* tweak format

---------

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

packages/frontend/src/components/page/page.image.vue

@@ -1,3 +1,8 @@
+<!--
+SPDX-FileCopyrightText: syuilo and other misskey contributors
+SPDX-License-Identifier: AGPL-3.0-only
+-->
+
 <template>
 <div>
 	<ImgWithBlurhash v-if="image" style="max-width: 100%;" :hash="image.blurhash" :src="image.url" :alt="image.comment" :title="image.comment" :width="image.properties.width" :height="image.properties.height" :cover="false"/>