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/sww/healthcheck_test.go

@@ -33,9 +33,9 @@ func TestHealthCheckInWAFsContainer(t *testing.T) {
 	out := &output{}
 	exited := make(chan int, 1)
 	settings := map[string]string{
-		listenAddr: localhost + ":0",
-		stateDir:   t.TempDir(),
-		rulesDir:   t.TempDir(),
+		listenAddr:   localhost + ":0",
+		stateDir:     t.TempDir(),
+		ruleFilesDir: t.TempDir(),
 	}
 
 	go func() {
@@ -120,7 +120,12 @@ func TestHealthCheckInRProxysContainer(t *testing.T) {
 
 	// Another setting does not fail it, even an invalid one, and neither does
 	// SWW_RPROXY_WAF_BACKEND being unset.
-	wantHealthCheck(t, settings("SWW_RPROXY_TIMEOUT_MS", "soon"), 0, "")
+	wantHealthCheck(
+		t,
+		settings("SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS", "soon"),
+		0,
+		"",
+	)
 
 	// Another test can take a closed server's port at once, so the app's
 	// address here is a multicast address, to which TCP cannot connect.