Need api for antvirus file handling

[iav]

Need api for handling stored files and filed just in time of uploading.
Need a way to tell user about server rejected file uploading because of antivirus report.

Other case - correctly enumerate by antivirus scanner all files stored for server or channel, and correctly move it from matrix server file storage to another file storage, and notify related administrators (file-own chats, servers, users etc).

Maybe some already used antivirus plug in protocols can be used - like milter or icap.

[hawkowl]

@ara4n don't we have this for dinsic or something now?

[dklimpel]

There is a hook for this case #9311