servewaf always answers rproxy well within its time limit (closes #182)

A question waits on GeoJS at most 800ms, the new default of
SWWAF_LOOKUP_TIMEOUT. It does not wait at all when the checks will refuse
it whatever GeoJS answers. Just before the Core Rule Set, servewaf refuses
more than 50 cookies or 100 header fields with 431.

Shared default changed: SWWAF_LOOKUP_TIMEOUT also applies to smallwebwaf
with no command.
Judgement call: SWWAF_REPUTATION_TIMEOUT stays 2s, since no request waits
on the DNS blocklists or AbuseIPDB.

Model: opus-5-5

internal/proxy/lookup_test.go

@@ -383,8 +383,8 @@ func TestRequestWaitsAsLongAsTheLookupTimeoutSays(t *testing.T) {
 	// network, which would keep that clock from moving on: the request is
 	// handed to the proxy's handler, and GeoJS is one that never answers.
 	synctest.Test(t, func(t *testing.T) {
-		// Not the default second. The exclusive list needs the answer, and
-		// the app is never reached.
+		// Not the default. The exclusive list needs the answer, and the app
+		// is never reached.
 		const timeout = 3 * time.Second
 
 		server, out, _ := newProxy(t, "http://app.invalid", unansweredGeoJSURL,