Add archive promotion locks

internal/config/validate.go

@@ -152,6 +152,23 @@ func validateArchive(cfg *ArchiveConfig, scriptorium *ScriptoriumConfig) error {
 		}
 		seenDest[normalizedDest] = struct{}{}
 	}
+	seenLocks := map[string]struct{}{}
+	for i, item := range cfg.Locks {
+		prefix := fmt.Sprintf("pipeline.archive.locks[%d]", i)
+		source := strings.TrimSpace(item.Source)
+		if source == "" {
+			return fmt.Errorf("%s.source is required", prefix)
+		}
+		if _, err := archiveSourceKnown(source, scriptorium); err != nil {
+			return fmt.Errorf("%s.source %q is unsupported: %w", prefix, item.Source, err)
+		}
+		if _, ok := seenLocks[source]; ok {
+			return fmt.Errorf("%s.source %q duplicates another archive lock source", prefix, source)
+		}
+		seenLocks[source] = struct{}{}
+		cfg.Locks[i].Source = source
+		cfg.Locks[i].Reason = strings.TrimSpace(item.Reason)
+	}
 	return nil
 }