feat: links to folders open as folders, on machines and SSH hosts, with their own icon; deleting a link leaves what it leads to

internal/proto/proto.go

@@ -292,6 +292,8 @@ type FSEntry struct {
 	Size  int64  `json:"size"`
 	Mode  string `json:"mode"`
 	MTime int64  `json:"mtime"`
+	// Link: a symbolic link (IsDir then says where it leads: a folder).
+	Link bool `json:"link,omitempty"`
 }
 
 // FSListResult is returned for TaskFSList.