enhance: AVIF support (#9281)

* chore: Make image/avif browsersafe

* server side

* change FileInfoService

* ✌️

* avifはMastodonでは絶望的 see https://github.com/misskey-dev/misskey/issues/9283

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

packages/backend/src/misc/is-mime-image.ts

@@ -2,7 +2,7 @@ import { FILE_TYPE_BROWSERSAFE } from '@/const.js';
 
 const dictionary = {
 	'safe-file': FILE_TYPE_BROWSERSAFE,
-	'sharp-convertible-image': ['image/jpeg', 'image/png', 'image/gif', 'image/apng', 'image/vnd.mozilla.apng', 'image/webp', 'image/svg+xml'],
+	'sharp-convertible-image': ['image/jpeg', 'image/png', 'image/gif', 'image/apng', 'image/vnd.mozilla.apng', 'image/webp', 'image/avif', 'image/svg+xml'],
 };
 
 export const isMimeImage = (mime: string, type: keyof typeof dictionary): boolean => dictionary[type].includes(mime);