Add more and details info to corpus in corpus management page - file listing

Problem to solve

Show more relevant info to help the user understand the corpus more and decide to choose to add/edit or remove corpus

Proposal

Design figma:https://www.figma.com/file/eSIeuIPKFwEDs4X9ky2O5E/Corpus-Registry?node-id=661%3A0

• Each corpus can be expanded and show all files
• Tell the user how many files contained in this corpus to give the user a quick overview