Mark signed zones with a padlock, and name clients in statistics

The zones list shows a padlock after signed zones, linking to their
DNSSEC tab. Client lists in the statistics show the host name Jarl's
records have for each address (PTR, else A/AAAA); no DNS queries.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/stats/query.go

@@ -128,7 +128,7 @@ func sorted(m map[string]int64, prefix string) []Entry {
 	out := []Entry{}
 	for k, v := range m {
 		if strings.HasPrefix(k, prefix) && v != 0 {
-			out = append(out, Entry{strings.TrimPrefix(k, prefix), v})
+			out = append(out, Entry{Key: strings.TrimPrefix(k, prefix), Count: v})
 		}
 	}
 	slices.SortFunc(out, func(a, b Entry) int {