feat(restore): 恢复前默认为当前世界做安全快照并串接恢复 Job，快照失败则不恢复；并发恢复另一备份返回 409

cmd/felis/backup_test.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+// The reason decides which backups the new one's prune may remove, so an
+// unknown one is refused before anything is archived.
+func TestBackupSubcommandRejectsUnknownReason(t *testing.T) {
+	var stderr bytes.Buffer
+	if code := cmdBackup([]string{"--server", "survival", "--reason", "inactive_15d"}, &bytes.Buffer{}, &stderr); code != 2 {
+		t.Fatalf("exit = %d, want 2 (%s)", code, stderr.String())
+	}
+	if !strings.Contains(stderr.String(), "unknown --reason") {
+		t.Fatalf("stderr = %q", stderr.String())
+	}
+}