just use dd with option conv=fsync and a reasonable blocksize like bs=1M. make sure you know which ssd is the one you read from and which you write to. command lsblk might be helpful here.
I dont know about kanban but the other stuff can be achieved via webdav. All major webservers can do that or you just use filebrowser.org (a selfhosted webdav server with built-in user management).