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. In enforce mode it does not wait at all when it is
over the header limits, on a fetched blocklist with deny, on the CrowdSec
decision list, or over a whole rate limit. Not waiting never lowers a
client's limit. 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/config/config_test.go

@@ -281,7 +281,7 @@ func TestDefaults(t *testing.T) {
 		RulesEnabled:                true,
 	})
 	wantLookupSettings(t, cfg, config.Config{
-		LookupSource: defaultLookupSource, LookupTimeout: time.Second,
+		LookupSource: defaultLookupSource, LookupTimeout: 800 * time.Millisecond,
 	})
 	wantByteLimitSettings(t, cfg, config.Config{
 		BytesLimitPerMinute: 4 << 30, BytesLimitPerHour: 20 << 30,
@@ -1165,7 +1165,7 @@ func TestLookupSettingsAsSet(t *testing.T) {
 
 	cfg = fromEnvironment(t, environment{lookupSource: off})
 	wantLookupSettings(t, cfg, config.Config{
-		LookupSource: off, LookupTimeout: time.Second,
+		LookupSource: off, LookupTimeout: 800 * time.Millisecond,
 	})
 }
 
@@ -2385,7 +2385,7 @@ func TestLogsEachSettingWithItsValue(t *testing.T) {
 		bytesCount:              "both",
 		lookupSource:            defaultLookupSource,
 		lookupDBPath:            "",
-		lookupTimeout:           "1s",
+		lookupTimeout:           "800ms",
 		addLookupHeaders:        "false",
 		deniedCountries:         "",
 		allowedCountries:        "",