Ban notes name the reputation sources that listed the client (closes #109)

A ban's notes, in bans.json and in its alert, gain `reputation`: each
blocklist, DNSBL zone or AbuseIPDB that listed the client when the ban
was made, as its `source`, named and ordered as in the request log's
`reputation`, with AbuseIPDB's `score`. It is left out when none did.
README.md shows it in a bans.json example.

Notes now hold a list, so bans can no longer be compared with ==: the
tests compare them with reflect.DeepEqual.

Judgement call: the score is a pointer, so a score of 0, a hit while
SWWAF_ABUSEIPDB_MIN_SCORE is 0, is still written.

Model: opus-5-5

internal/proxy/admin_test.go

@@ -4,7 +4,7 @@ import (
 	"encoding/json"
 	"net/http"
 	"net/netip"
-	"slices"
+	"reflect"
 	"strconv"
 	"strings"
 	"testing"
@@ -48,7 +48,7 @@ func TestAdminEndpointsAreOffWhileTheTokenIsUnset(t *testing.T) {
 		}
 	}
 
-	if after := server.Ledger.Snapshot(); !slices.Equal(after, before) {
+	if after := server.Ledger.Snapshot(); !reflect.DeepEqual(after, before) {
 		t.Errorf("the bans are now\n%+v\nwant them unchanged\n%+v", after, before)
 	}
 }
@@ -79,7 +79,7 @@ func TestAdminEndpointsNeedTheAdminToken(t *testing.T) {
 			}
 		}
 
-		if after := server.Ledger.Snapshot(); !slices.Equal(after, before) {
+		if after := server.Ledger.Snapshot(); !reflect.DeepEqual(after, before) {
 			t.Errorf("%s %s without the token changed the bans to\n%+v\nfrom\n%+v",
 				e.method, e.path, after, before)
 		}