feat(server): activate projected authentication safely

tools/tht/internal/backup/restore_projection_unsupported.go

@@ -0,0 +1,9 @@
+//go:build !linux
+
+package backup
+
+import "errors"
+
+func requireAuthProjectionRestorePrivilege() error {
+	return errors.New("projected authentication restore is unsupported")
+}