[fix] .wav .flac ファイルを再生可能にする (#10686)

* .wav .flac ファイルを再生可能にする
file-typeにより判定されたMIME TypeをHTML5 Audio/Video要素に認識されるものに書き換える

* fix typecheck error

* frontend側の FILE_TYPE_BROWSERSAFEも更新

* Update packages/backend/src/core/FileInfoService.ts

* ✌️

* 後方互換を確保

* add tests

* update changelog.md

---------

Co-authored-by: tamaina <tamaina@hotmail.co.jp>

packages/backend/src/core/FileInfoService.ts

@@ -5,7 +5,7 @@ import * as stream from 'node:stream';
 import * as util from 'node:util';
 import { Injectable } from '@nestjs/common';
 import { FSWatcher } from 'chokidar';
-import { fileTypeFromFile } from 'file-type';
+import * as fileType from 'file-type';
 import FFmpeg from 'fluent-ffmpeg';
 import isSvg from 'is-svg';
 import probeImageSize from 'probe-image-size';
@@ -301,21 +301,34 @@ export class FileInfoService {
 		return fs.promises.access(path).then(() => true, () => false);
 	}
 
+	@bindThis
+	public fixMime(mime: string | fileType.MimeType): string {
+		// see https://github.com/misskey-dev/misskey/pull/10686
+		if (mime === "audio/x-flac") {
+			return "audio/flac";
+		}
+		if (mime === "audio/vnd.wave") {
+			return "audio/wav";
+		}
+
+		return mime;
+	}
+
 	/**
 	 * Detect MIME Type and extension
 	 */
 	@bindThis
 	public async detectType(path: string): Promise<{
-	mime: string;
-	ext: string | null;
-}> {
+		mime: string;
+		ext: string | null;
+	}> {
 	// Check 0 byte
 		const fileSize = await this.getFileSize(path);
 		if (fileSize === 0) {
 			return TYPE_OCTET_STREAM;
 		}
 
-		const type = await fileTypeFromFile(path);
+		const type = await fileType.fileTypeFromFile(path);
 
 		if (type) {
 		// XMLはSVGかもしれない
@@ -324,7 +337,7 @@ export class FileInfoService {
 			}
 
 			return {
-				mime: type.mime,
+				mime: this.fixMime(type.mime),
 				ext: type.ext,
 			};
 		}