Internet exposure checks and response rate limiting

Jarl works out which views are reachable from the internet (match-clients
ending in a catch-all, not private-looking addresses: an internal view of a
global IPv6 prefix is still yours; a server without views: open allow-query
and a non-private listen address), with a per-view override (schema 9), and
checks public ones: rate limiting, open resolver, minimal-any, cache
snooping, open NOTIFY and transfers, version and host name, management
interfaces. Fixes are staged like any change, including rate limiting from
ISC's example in log-only mode with the secondaries exempt, then enforcing.
named logs what rate limiting limits (or would, in log-only mode, where its
counters don't move) as query-errors; Jarl routes those lines to its log
and counts them (rrl breakdown, ratelimited top lists, Prometheus
jarl_ratelimit_logged_total), shown on the new Exposure page.

A change that newly opens a public view up must be confirmed (accept_risk,
--accept-risk, a checkbox on the Changes page; 409 confirm_risk
otherwise). Findings can be acknowledged with a reason and stay visible as
info. GET /exposure, POST /exposure/fix|ack|unack, jarl exposure,
docs/exposure.md.

Also fixes query statistics skipping TSIG-signed queries ("IP#port/key
NAME" in named's log).

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

internal/store/state.go

@@ -31,20 +31,23 @@ func loadState(ctx context.Context, e execer) (*model.State, error) {
 		}
 	}
 
-	rows, err := e.QueryContext(ctx, `SELECT id, name, position, match_clients, match_destinations, match_recursive_only, comment, version, created_at, updated_at, created_by, updated_by FROM views`)
+	rows, err := e.QueryContext(ctx, `SELECT id, name, position, match_clients, match_destinations, match_recursive_only, comment, exposure, acknowledged, version, created_at, updated_at, created_by, updated_by FROM views`)
 	if err != nil {
 		return nil, err
 	}
 	for rows.Next() {
 		v := &model.View{}
-		var mc, md, ca, ua string
+		var mc, md, acks, ca, ua string
 		var mro sql.NullInt64
-		if err := rows.Scan(&v.ID, &v.Name, &v.Position, &mc, &md, &mro, &v.Comment, &v.Version, &ca, &ua, &v.CreatedBy, &v.UpdatedBy); err != nil {
+		if err := rows.Scan(&v.ID, &v.Name, &v.Position, &mc, &md, &mro, &v.Comment, &v.Exposure, &acks, &v.Version, &ca, &ua, &v.CreatedBy, &v.UpdatedBy); err != nil {
 			rows.Close()
 			return nil, err
 		}
 		json.Unmarshal([]byte(mc), &v.MatchClients)
 		json.Unmarshal([]byte(md), &v.MatchDestinations)
+		if acks != "[]" && acks != "" {
+			json.Unmarshal([]byte(acks), &v.Acknowledged)
+		}
 		if mro.Valid {
 			v.MatchRecursiveOnly = model.Ptr(mro.Int64 != 0)
 		}
@@ -264,8 +267,8 @@ func saveState(ctx context.Context, e execer, old, new *model.State) error {
 		if v.MatchRecursiveOnly != nil {
 			mro = boolInt(*v.MatchRecursiveOnly)
 		}
-		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO views (id, name, position, match_clients, match_destinations, match_recursive_only, comment, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?,?)`,
-			v.ID, v.Name, v.Position, jsonText(nonNil(v.MatchClients)), jsonText(nonNil(v.MatchDestinations)), mro, v.Comment, v.Version, ts(v.CreatedAt), ts(v.UpdatedAt), v.CreatedBy, v.UpdatedBy)
+		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO views (id, name, position, match_clients, match_destinations, match_recursive_only, comment, exposure, acknowledged, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?)`,
+			v.ID, v.Name, v.Position, jsonText(nonNil(v.MatchClients)), jsonText(nonNil(v.MatchDestinations)), mro, v.Comment, v.Exposure, jsonText(nonNilAcks(v.Acknowledged)), v.Version, ts(v.CreatedAt), ts(v.UpdatedAt), v.CreatedBy, v.UpdatedBy)
 		return err
 	}, func(id int64) error { return del(ctx, e, "views", id) }); err != nil {
 		return err
@@ -344,6 +347,13 @@ func nonNilIDs(ids []int64) []int64 {
 	return ids
 }
 
+func nonNilAcks(a []model.Acknowledgement) []model.Acknowledgement {
+	if a == nil {
+		return []model.Acknowledgement{}
+	}
+	return a
+}
+
 func nonNil(s []string) []string {
 	if s == nil {
 		return []string{}