Name log fields, metrics and the Core Rule Set package for what they are (closes #192)

Log field, metric, action and event names now say what they count
and, for timings, the unit. Package internal/waf is internal/coreruleset.

Model: opus-5-5

internal/discriminator/metrics_test.go

@@ -91,7 +91,7 @@ func TestMetricsCountTheTraffic(t *testing.T) {
 	out.endedLines(t, 2)
 
 	forward := `{action="forward",instance="app",status_class="2xx"}`
-	notFound := `{action="admin",instance="app",status_class="4xx"}`
+	notFound := `{action="own_endpoint",instance="app",status_class="4xx"}`
 
 	// The request for the metrics is itself under way.
 	metrics := scrape(t, server.Addr)
@@ -347,7 +347,7 @@ func TestMetricsCountGeoJSRequestsAndFailures(t *testing.T) {
 
 	wantMetric(t, metrics, `sww_geojs_requests_total{instance="app"}`, 1)
 	wantMetric(t, metrics, `sww_geojs_failures_total{instance="app"}`, 1)
-	wantMetric(t, metrics, `sww_geojs_unanswered_total{instance="app"}`, 1)
+	wantMetric(t, metrics, `sww_requests_without_geojs_answer_total{instance="app"}`, 1)
 }
 
 // keptAnswer returns GeoJS's answer that the client at addr is in