Mapping paths had to be typed. The local path and deployment path cells now have a folder button: the local one picks a folder inside the project, the deployment one opens the server's folder chooser at its root path, and both fill in the path relative to their root (the deployment button needs an absolute root path).
Fixes#799
Deployment only supported SFTP, so a web root on the same machine or on a mounted share still needed an SSH server.
Servers now have a type: SFTP or Local or mounted folder. A local server has a folder and optional web URL and shares upload on save, upload and download, delete, compare and sync, excludes, mappings and the Remote Host view with SFTP through one backend filesystem. Copies never read the whole file into memory, a file is never copied onto itself, and Test Connection checks the folder exists and is writable. Existing servers stay SFTP.
Fixes#467
l0ng-ai