Function createMockMediaFile

Returns {
    createdAt: string;
    duration: number;
    extension: string;
    id: string;
    isAudio: boolean;
    isImage: boolean;
    isVideo: boolean;
    name: string;
    path: string;
    probeData: {
        format: { duration: number };
        streams: { codec_type: string }[];
    };
    size: number;
}