Pause blocking, blocked clients and a blocked line in the statistics, compact view picker

jarl block pause|resume (and the Blocking page) lets every name through
for a while; jarld resumes on time. The lists stay loaded: the rules zone
just passes everything. Statistics gain the clients with the most blocked
queries and blocked queries on the queries chart. The view choice in the
blocking forms is a dropdown.

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

internal/stats/blocking_test.go

@@ -93,6 +93,9 @@ func TestCollectorBlocking(t *testing.T) {
 	if b, _ := store.TopsAt(ctx, ResHour, m, KindBlocked); len(b) != 2 || b[0] != (Entry{Key: "ads.example", Count: 2}) {
 		t.Errorf("blocked names = %v", b)
 	}
+	if bc, _ := store.TopsAt(ctx, ResHour, m, KindBlockedClient); len(bc) != 2 || bc[0] != (Entry{Key: "10.0.0.5", Count: 2}) {
+		t.Errorf("blocked clients = %v", bc)
+	}
 	if nx, _ := store.TopsAt(ctx, ResHour, m, KindNXDomain); len(nx) != 1 || nx[0].Key != "typo.example" {
 		t.Errorf("NXDOMAIN names should leave out blocked ones: %v", nx)
 	}