Rename the program to sww and its deciding daemon to discriminator

The program is now sww, built from cmd/sww, with two modes: sww rproxy and
sww discriminator. servewaf becomes discriminator everywhere it names that
daemon: the package (internal/discriminator), its types, functions, files, the
discriminator_line log field, and its docs and tests.

smallwebwaf is left only where sneak's directive allows it: the documents'
product name, the git.eeqj.de/sneak/smallwebwaf URLs, and the Go module path
sneak.berlin/go/smallwebwaf. Everywhere else a name containing it takes the sww
form: the package (internal/sww), metric names (sww_*), the X-Sww-* headers,
the /_sww/ admin endpoints, the SWW_COMMAND setting, the OS user, and the state
and rules directories.

No logic changes. make check passes.

Model: deepseek-v4-pro

internal/reputation/abuseipdb_test.go

@@ -397,7 +397,7 @@ func TestMetricsCountTheChecksTheFailuresAndTheBudgetLeft(t *testing.T) {
 			"failures_total":         "1",
 			"daily_budget_remaining": "3",
 		} {
-			line := "\nsmallwebwaf_reputation_" + series +
+			line := "\nsww_reputation_" + series +
 				`{instance="app",source="abuseipdb"} ` + want + "\n"
 			if !strings.Contains(scraped, line) {
 				t.Errorf("metrics\n%s\nwant%s", scraped, line)
@@ -581,7 +581,7 @@ func wantScore(
 
 // hitFrom is checker's Hit for a request from address, offender or not.
 // Its client is address for an IPv4 address, and its /64 for an IPv6 one,
-// as smallwebwaf counts clients.
+// as sww counts clients.
 func hitFrom(
 	t *testing.T, checker *reputation.AbuseIPDB, address string, offender bool,
 ) (int64, bool) {

internal/reputation/dnsbl_test.go

@@ -311,7 +311,7 @@ func TestMetricsCountEachZonesQueriesAndThoseThatFailed(t *testing.T) {
 			"queries_total" + `{instance="app",source="` + otherZone + `"}`:  "1",
 			"failures_total" + `{instance="app",source="` + otherZone + `"}`: "1",
 		} {
-			line := "\nsmallwebwaf_reputation_" + series + " " + want + "\n"
+			line := "\nsww_reputation_" + series + " " + want + "\n"
 			if !strings.Contains(scraped.Body.String(), line) {
 				t.Errorf("metrics\n%s\nwant%s", scraped.Body.String(), line)
 			}

internal/reputation/reputation.go

@@ -371,7 +371,7 @@ func (l *Lists) due(listURL string) time.Time {
 // fetch fetches the list at listURL, and notes the try. A good copy takes
 // the place of the one held. A failure leaves that in use, and is counted,
 // logged and raised as a source_failure alert. A fetch cut off as ctx
-// ends, as smallwebwaf stops, is no failure, but is still noted as a try,
+// ends, as sww stops, is no failure, but is still noted as a try,
 // so that a restart waits for it: the server may have had its request.
 func (l *Lists) fetch(ctx context.Context, listURL string) {
 	lines, err := l.get(ctx, listURL)