Read SWWAF_IPV6_GROUP_PREFIX, SWWAF_MAX_TRACKED_CLIENTS and SWWAF_LOG_LEVEL (closes #112)

The IPv6 group that is one client, the size of the table of clients and
the level of the process's own lines become settings. clientGroup reads
the group length from them, so limits, bans, history, lookups, AbuseIPDB
scores and per-client anomaly counters all follow it; ratelimit.New
takes the table size; the process logger takes the level once the
settings are read, and request lines, written apart from it, are never
held back.

Judgement call: SWWAF_IPV6_GROUP_PREFIX accepts 32 to 128, the issue's example range.

Model: opus-5-5

internal/proxy/bans.go

@@ -45,7 +45,7 @@ func (rq *request) banned(now time.Time) bool {
 // the client over a rate limit, as its limit percentage lowers it, which
 // breaks it.
 func (rq *request) limitBroken(now time.Time) bool {
-	counts, hit, over := rq.h.limiter.Count(clientGroup(rq.client), now,
+	counts, hit, over := rq.h.limiter.Count(rq.h.clientGroup(rq.client), now,
 		rq.limitPercent.percent)
 	rq.line.Counts = counts
 
@@ -71,7 +71,7 @@ func (rq *request) countBytes() {
 
 	now := rq.h.now()
 
-	counts, hit, over := rq.h.limiter.CountBytes(clientGroup(rq.client), now,
+	counts, hit, over := rq.h.limiter.CountBytes(rq.h.clientGroup(rq.client), now,
 		rq.countedBytes(), rq.bytesPercent.percent)
 	rq.line.Counts.MinuteBytes = counts.MinuteBytes
 	rq.line.Counts.HourBytes = counts.HourBytes
@@ -155,7 +155,7 @@ func (rq *request) banForLimit(now time.Time, hit ratelimit.Hit, status int) {
 	}
 
 	ban, made := rq.h.ledger.BanForLimit(netblock, now, notes)
-	rq.h.limiter.Reset(clientGroup(rq.client))
+	rq.h.limiter.Reset(rq.h.clientGroup(rq.client))
 	rq.line.BanExpires = banExpires(ban)
 
 	if made {
@@ -276,7 +276,7 @@ func (h *handler) netblock(client netip.Addr) netip.Prefix {
 		return netip.PrefixFrom(addr, h.config.BanScopeV4Prefix).Masked()
 	}
 
-	return clientGroup(addr)
+	return h.clientGroup(addr)
 }
 
 // banExpires is when ban ends, as the log line gives it: a time, or