Extra FileCollectionItem information

[lpatiny]

I would like to be able to store a custom information about the file directly in the FileCollectionItem.

I propose to add in FileCollectionItem an optional property meta of type Record<string, any>

It will allow for the following methods:

• https://github.com/cheminfo/filelist-utils/blob/main/src/fileCollectionFromFileList.ts
• https://github.com/cheminfo/filelist-utils/blob/main/src/fileCollectionFromWebservice.ts

To copy this property if it is provided in the data source.

@targos Is it ok for you to add this property ?

This issue is related to cheminfo/nmrium#1775 for which we need to load a jcamp file that contains many spectra and we remember the index that should be considered