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/client/client.go

@@ -38,6 +38,9 @@ type Client struct {
 	csErr          error
 	DryRun         bool
 	Force          bool
+	// AcceptRisk confirms changes that open the server up
+	// (docs/exposure.md).
+	AcceptRisk bool
 	// Preflight lets only requests through that can't change anything:
 	// reads and dry runs. Running a command on several servers uses it to
 	// check the command everywhere before running it anywhere.
@@ -282,6 +285,9 @@ func (c *Client) Mutate(ctx context.Context, method, path string, query url.Valu
 	if c.Force {
 		q.Set("force", "1")
 	}
+	if c.AcceptRisk {
+		q.Set("accept_risk", "1")
+	}
 	var out api.MutationResponse
 	err = c.Do(ctx, method, path, q, body, &out)
 	return &out, err