Rename the settings whose names do not say what they control (closes #234)

Applies the setting renames of the naming audit under the SWW_WAF_ and
SWW_RPROXY_ prefixes, with sneak's names for the IP reputation cache
time and the two time limits, which now take milliseconds. The rproxy
log field default_disposition becomes waf_backend_no_answer, and
config.Config and config.FromEnvironment become config.WAF and
config.WAFFromEnvironment. Go fields, test names and prose follow. No
aliases; nothing reads the old names.

Model: opus-5-5

internal/waf/refusallimit_test.go

@@ -15,7 +15,7 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/waf"
 )
 
-const errorBurstThreshold = "SWW_WAF_ERROR_BURST_THRESHOLD"
+const refusalsLimitPerMinute = "SWW_WAF_REFUSALS_LIMIT_PER_MINUTE"
 
 // refused is a request the tests here send, which waf refuses after a rule
 // file match.
@@ -49,16 +49,16 @@ func (r refused) send(s *sender, from string) logLine {
 }
 
 // startForErrorBurst is startWithClock with testRules, the metrics token and
-// SWW_WAF_ERROR_BURST_THRESHOLD at threshold, and the settings in env.
+// SWW_WAF_REFUSALS_LIMIT_PER_MINUTE at threshold, and the settings in env.
 func startForErrorBurst(
 	t *testing.T, threshold string, env map[string]string,
 ) (*sender, *clock, *waf.Server) {
 	t.Helper()
 
 	settings := map[string]string{
-		errorBurstThreshold: threshold,
-		rulesDir:            writeRules(t, testRules),
-		metricsToken:        token,
+		refusalsLimitPerMinute: threshold,
+		ruleFilesDir:           writeRules(t, testRules),
+		metricsToken:           token,
 	}
 	maps.Copy(settings, env)
 
@@ -226,10 +226,10 @@ func TestErrorBurstIsNotLoweredForAClientWithLowerLimits(t *testing.T) {
 
 	geojsURL, _ := startGeoJS(t)
 	s, _, server := startWithClock(t, geojsURL, map[string]string{
-		lookupTimeout:       "1h",
-		errorBurstThreshold: "2",
-		rulesDir:            writeRules(t, testRules),
-		tagLimitPercent:     countryTagDEHalf,
+		asnAndCountryLookupTimeout: "3600000",
+		refusalsLimitPerMinute:     "2",
+		ruleFilesDir:               writeRules(t, testRules),
+		tagLimitPercent:            countryTagDEHalf,
 	})
 
 	// Half of the threshold would be one, which the second refusal is over.
@@ -266,8 +266,8 @@ func TestErrorBurstDoesNotCountTheAppsAnswers(t *testing.T) {
 			w.WriteHeader(statuses[r.URL.Path])
 		},
 		map[string]string{
-			errorBurstThreshold: "1",
-			rulesDir:            writeRules(t, testRules),
+			refusalsLimitPerMinute: "1",
+			ruleFilesDir:           writeRules(t, testRules),
 		},
 	)
 
@@ -298,18 +298,18 @@ func TestErrorBurstOffOrAtItsDefault(t *testing.T) {
 
 	for _, tc := range []struct {
 		threshold string
-		// broken is whether the 31st refusal breaks the error burst.
+		// broken is whether the 31st refusal breaks the refusal limit.
 		broken bool
 	}{
 		{"", true},
 		{off, false},
 	} {
-		t.Run(errorBurstThreshold+"="+tc.threshold, func(t *testing.T) {
+		t.Run(refusalsLimitPerMinute+"="+tc.threshold, func(t *testing.T) {
 			t.Parallel()
 
-			env := map[string]string{rulesDir: writeRules(t, testRules)}
+			env := map[string]string{ruleFilesDir: writeRules(t, testRules)}
 			if tc.threshold != "" {
-				env[errorBurstThreshold] = tc.threshold
+				env[refusalsLimitPerMinute] = tc.threshold
 			}
 
 			s, _, _ := startWithClock(t, "", env)
@@ -322,7 +322,7 @@ func TestErrorBurstOffOrAtItsDefault(t *testing.T) {
 			broken := line.LimitHit == requestlog.LimitHitMinuteRefusals
 			if broken != tc.broken {
 				t.Errorf(
-					"the 31st refusal broke the error burst: %t, want %t",
+					"the 31st refusal broke the refusal limit: %t, want %t",
 					broken,
 					tc.broken,
 				)
@@ -393,9 +393,9 @@ func TestObserveModeLogsAndAlertsTheErrorBurst(t *testing.T) {
 	t.Parallel()
 
 	s, clk, server, queue := startWithAlerts(t, map[string]string{
-		mode:                observe,
-		errorBurstThreshold: "1",
-		rulesDir:            writeRules(t, testRules),
+		mode:                   observe,
+		refusalsLimitPerMinute: "1",
+		ruleFilesDir:           writeRules(t, testRules),
 	})
 	start := clk.Now()
 	held := bans.Ban{