Request tags, with refusing and limits per tag (closes #175)

Each request gets sorted tags from the lookup, new address lists, the
reputation sources and the rule matches, logged as `tags`. New settings:
`SWW_TAG_LISTS`, `SWW_TAG_DENY`, `SWW_TAG_LIMIT_PERCENT`. They replace
`SWW_ASN_LIMIT_PERCENT`, `SWW_COUNTRY_LIMIT_PERCENT` and
`SWW_DENIED_COUNTRIES`. New heuristics `tag_lists` and `tag_deny`; the
latter runs before the rate limits and again after the Core Rule Set.

Model: opus-5-5

internal/discriminator/answertime_test.go

@@ -335,7 +335,7 @@ func newDiscriminatorInBubble(
 ) (*discriminator.Server, *output) {
 	t.Helper()
 
-	settings := map[string]string{deniedCountries: "KP"}
+	settings := map[string]string{tagDeny: "country=KP"}
 	maps.Copy(settings, env)
 
 	server, out, _ := newDiscriminator(t, unansweredGeoJSURL, time.Now, settings)
@@ -542,7 +542,7 @@ func TestDiscriminatorAnswersWithinTheTimeLimitWhileEveryOutsideSourceHangs(
 
 		return discriminator.New(params)
 	}, held, time.Now, map[string]string{
-		deniedCountries: "KP", wafMode: block,
+		tagDeny: "country=KP", wafMode: block,
 		dnsblZones: dnsblZone, dnsblResolver: resolver.LocalAddr().String(),
 		abuseIPDBKey:  accountKey,
 		blocklistURLs: held + "/drop.txt", asnLimitPercentURL: held + "/asn.txt",