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/server/routes.go

@@ -162,6 +162,10 @@ func (s *Server) routes() {
 	m.HandleFunc("POST "+p+"/acme/httpreq/view/{view}/present", s.httpreq(true))
 	m.HandleFunc("POST "+p+"/acme/httpreq/view/{view}/cleanup", s.httpreq(false))
 	// Query statistics
+	m.HandleFunc("GET "+p+"/exposure", s.authed(s.exposure))
+	m.HandleFunc("POST "+p+"/exposure/fix", s.authed(s.exposureFix))
+	m.HandleFunc("POST "+p+"/exposure/ack", s.authed(s.exposureAck(true)))
+	m.HandleFunc("POST "+p+"/exposure/unack", s.authed(s.exposureAck(false)))
 	m.HandleFunc("GET "+p+"/stats/status", s.authed(s.statsStatus))
 	m.HandleFunc("GET "+p+"/stats/summary", s.authed(s.statsSummary))
 	m.HandleFunc("GET "+p+"/stats/top", s.authed(s.statsTop))
@@ -252,7 +256,7 @@ func (s *Server) mutate(w http.ResponseWriter, r *http.Request, p *auth.Principa
 		writeJSON(w, http.StatusAccepted, api.MutationResponse{Staged: true, ChangesetID: csID, Changeset: raw(res.Changeset), Added: engine.RedactOps(res.Added), Warnings: res.Warnings, Problems: raw(res.Problems)})
 		return nil
 	}
-	opts := engine.ApplyOptions{DryRun: queryBool(r, "dry_run"), Force: queryBool(r, "force")}
+	opts := engine.ApplyOptions{DryRun: queryBool(r, "dry_run"), Force: queryBool(r, "force"), AcceptRisk: queryBool(r, "accept_risk")}
 	res, err := s.eng.Submit(r.Context(), reqs, p, via(r, p), description, opts)
 	if err != nil {
 		s.writeErr(w, r, err, res)