SFTP: copy file/dir path in the interface

[Eugeny]

Discussed in https://github.com/Eugeny/tabby/discussions/6865

^{Originally posted by Yelijah July 29, 2022} I what to copy file path in the sftp interface. But sftp's address bar can't allow me to copy. And when i right click on file or dir， the right menu has no 'copy path' item. I think it's a very useful and normal operation.