Add DNSSEC signing, key backups and Porkbun support

Zones get a DNSSEC setting: named signs them with BIND's default (or a
custom) dnssec-policy and inline signing, with keys in a per-view key
directory. Jarl shows the keys, the DS record and when it is safe to
publish it, checks the parent's DS records (check-ds, which also tells
named), and refuses steps that would break a signed domain: switching
straight to unsigned, finishing a turn-off too early, deleting or moving
a signed zone, TTLs above max-zone-ttl. Turning off goes through the
insecure policy; wipe starts over once the parent has no DS.

Backups store the DNSSEC keys and restore puts them back for named; the
backup unit gets CAP_DAC_READ_SEARCH to read them. Jarl raises a zone's
serial above named's whenever it writes an older one (after a restore).
The serials check compares the signed serial.

With a Porkbun API key in jarl.yaml, the registrar's name servers, glue
records and DS records can be shown and changed, each change checked
first (dry run, force to override).

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

internal/store/state.go

@@ -92,14 +92,14 @@ func loadState(ctx context.Context, e execer) (*model.State, error) {
 		return nil, err
 	}
 
-	rows, err = e.QueryContext(ctx, `SELECT id, name, view_id, type, in_view, file, soa_mname, soa_rname, soa_serial, soa_refresh, soa_retry, soa_expire, soa_minimum, default_ttl, serial_policy, comment, version, created_at, updated_at, created_by, updated_by FROM zones`)
+	rows, err = e.QueryContext(ctx, `SELECT id, name, view_id, type, in_view, file, soa_mname, soa_rname, soa_serial, soa_refresh, soa_retry, soa_expire, soa_minimum, default_ttl, serial_policy, dnssec_policy, comment, version, created_at, updated_at, created_by, updated_by FROM zones`)
 	if err != nil {
 		return nil, err
 	}
 	for rows.Next() {
 		z := &model.Zone{}
 		var ca, ua string
-		if err := rows.Scan(&z.ID, &z.Name, &z.ViewID, &z.Type, &z.InView, &z.File, &z.SOA.MName, &z.SOA.RName, &z.SOA.Serial, &z.SOA.Refresh, &z.SOA.Retry, &z.SOA.Expire, &z.SOA.Minimum, &z.DefaultTTL, &z.SerialPolicy, &z.Comment, &z.Version, &ca, &ua, &z.CreatedBy, &z.UpdatedBy); err != nil {
+		if err := rows.Scan(&z.ID, &z.Name, &z.ViewID, &z.Type, &z.InView, &z.File, &z.SOA.MName, &z.SOA.RName, &z.SOA.Serial, &z.SOA.Refresh, &z.SOA.Retry, &z.SOA.Expire, &z.SOA.Minimum, &z.DefaultTTL, &z.SerialPolicy, &z.DNSSECPolicy, &z.Comment, &z.Version, &ca, &ua, &z.CreatedBy, &z.UpdatedBy); err != nil {
 			rows.Close()
 			return nil, err
 		}
@@ -209,8 +209,8 @@ func saveState(ctx context.Context, e execer, old, new *model.State) error {
 		return err
 	}
 	if err := diffMap(old.Zones, new.Zones, func(z *model.Zone) error {
-		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO zones (id, name, view_id, type, in_view, file, soa_mname, soa_rname, soa_serial, soa_refresh, soa_retry, soa_expire, soa_minimum, default_ttl, serial_policy, comment, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)`,
-			z.ID, z.Name, z.ViewID, z.Type, z.InView, z.File, z.SOA.MName, z.SOA.RName, z.SOA.Serial, z.SOA.Refresh, z.SOA.Retry, z.SOA.Expire, z.SOA.Minimum, z.DefaultTTL, z.SerialPolicy, z.Comment, z.Version, ts(z.CreatedAt), ts(z.UpdatedAt), z.CreatedBy, z.UpdatedBy)
+		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO zones (id, name, view_id, type, in_view, file, soa_mname, soa_rname, soa_serial, soa_refresh, soa_retry, soa_expire, soa_minimum, default_ttl, serial_policy, dnssec_policy, comment, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)`,
+			z.ID, z.Name, z.ViewID, z.Type, z.InView, z.File, z.SOA.MName, z.SOA.RName, z.SOA.Serial, z.SOA.Refresh, z.SOA.Retry, z.SOA.Expire, z.SOA.Minimum, z.DefaultTTL, z.SerialPolicy, z.DNSSECPolicy, z.Comment, z.Version, ts(z.CreatedAt), ts(z.UpdatedAt), z.CreatedBy, z.UpdatedBy)
 		return err
 	}, func(id int64) error { return del(ctx, e, "zones", id) }); err != nil {
 		return err