AS number and country looked up for every client (closes #95)

GeoJS's geo.json is asked about every new visitor unless
SWWAF_LOOKUP_SOURCE is off. A request waits for its client's first
answer only while a country list or SWWAF_ADD_LOOKUP_HEADERS needs it;
otherwise the answer reaches the client's history and ban notes when it
comes. The AS number and name go beside the country in the request log,
history, ban notes, alerts and lookups.json, with metrics by AS number;
64512 counts as unknown. A client's own X-Client-ASN and
X-Client-Country never reach the app, whatever the setting says, and
make example-app sends no address to GeoJS.

Judgement call: AS numbers are written AS64496, as SPEC's settings write them.
Judgement call: SWWAF_LOOKUP_TIMEOUT is added, default 1s, and cannot be off.

Model: opus-5-5

internal/proxy/proxy.go

@@ -54,8 +54,8 @@ type Params struct {
 	RequestLog io.Writer
 	// ProcessLog receives the process's own messages.
 	ProcessLog *slog.Logger
-	// GeoJSURL is where clients' countries are looked up, normally
-	// lookup.URL. GeoJS is asked only while a country list is set.
+	// GeoJSURL is where clients' AS numbers and countries are looked up,
+	// normally lookup.URL, unless SWWAF_LOOKUP_SOURCE is off.
 	GeoJSURL string
 	// Now tells the time by which requests are counted for the rate
 	// limits, bans are made and run out, and GeoJS's answers are kept,
@@ -109,16 +109,23 @@ func New(params Params) *Server {
 			AttackBanDuration:    params.Config.AttackBanDuration,
 			MaxBans:              params.Config.MaxBans,
 		}),
-		geojs: lookup.New(lookup.Params{
-			URL:        params.GeoJSURL,
-			Now:        params.Now,
-			ProcessLog: params.ProcessLog,
-			Metrics:    m,
-			Alerts:     params.Alerts,
-		}),
 		rules:  params.Rules,
 		alerts: params.Alerts,
 	}
+	h.geojs = lookup.New(lookup.Params{
+		URL:     params.GeoJSURL,
+		Timeout: params.Config.LookupTimeout,
+		// The country lists and the headers act on the answer before the
+		// request goes on.
+		Wait: len(params.Config.DeniedCountries) > 0 ||
+			len(params.Config.ExclusivelyAllowedCountries) > 0 ||
+			params.Config.AddLookupHeaders,
+		Answered:   h.addLookup,
+		Now:        params.Now,
+		ProcessLog: params.ProcessLog,
+		Metrics:    m,
+		Alerts:     params.Alerts,
+	})
 	m.AddBansAndClients(h.ledger, h.limiter, params.Now)
 	m.AddRules(params.Rules)