rproxy passes the app the client's AS number and country by default (closes #379)

SWW_WAF_ADD_LOOKUP_HEADERS now defaults to true, so the app gets
X-Client-ASN and X-Client-Country with no setting. While
SWW_WAF_LOOKUP_SOURCE is off it defaults to false, so turning lookups
off alone still starts; true set with the lookup off still stops the
start. With GeoJS, a new client's first request now waits for its
answer, up to SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS.

Model: opus-5-5

internal/config/waf_test.go

@@ -287,6 +287,7 @@ func TestDefaults(t *testing.T) {
 	})
 	wantLookupSettings(t, cfg, config.WAF{
 		LookupSource: defaultLookupSource, ASNAndCountryLookupTimeout: 800 * time.Millisecond,
+		AddLookupHeaders: true,
 	})
 	wantByteLimitSettings(t, cfg, config.WAF{
 		BytesLimitPerMinute: 0, BytesLimitPerHour: 50 << 30,
@@ -1395,13 +1396,13 @@ func TestLookupSettingsAsSet(t *testing.T) {
 	t.Parallel()
 
 	cfg := wafFromEnvironment(t, environment{
-		asnAndCountryLookupTimeout: "500", addLookupHeaders: enabled,
+		asnAndCountryLookupTimeout: "500", addLookupHeaders: disabled,
 	})
 	wantLookupSettings(t, cfg, config.WAF{
 		LookupSource: defaultLookupSource, ASNAndCountryLookupTimeout: 500 * time.Millisecond,
-		AddLookupHeaders: true,
 	})
 
+	// With no client looked up, the headers are off unless set.
 	cfg = wafFromEnvironment(t, environment{lookupSource: off})
 	wantLookupSettings(t, cfg, config.WAF{
 		LookupSource: off, ASNAndCountryLookupTimeout: 800 * time.Millisecond,
@@ -1422,6 +1423,10 @@ func TestLookupDBPathGoesWithTheFileSourceAlone(t *testing.T) {
 			cfg.LookupSource, cfg.LookupDBPath, path)
 	}
 
+	if !cfg.AddLookupHeaders {
+		t.Error("headers off by default with lookups from file, want on")
+	}
+
 	for _, tc := range []struct {
 		env  environment
 		want string
@@ -2927,7 +2932,7 @@ func TestLogsEachSettingWithItsValue(t *testing.T) {
 		lookupSource:                   defaultLookupSource,
 		lookupDBPath:                   "",
 		asnAndCountryLookupTimeout:     "800",
-		addLookupHeaders:               disabled,
+		addLookupHeaders:               enabled,
 		allowedCountries:               "",
 		tagLists:                       "",
 		tagDeny:                        "",