Rename the settings whose names do not say what they control (closes #234)

Applies the setting renames of the naming audit under the SWW_WAF_ and
SWW_RPROXY_ prefixes, with sneak's names for the IP reputation cache
time and the two time limits, which now take milliseconds. The rproxy
log field default_disposition becomes waf_backend_no_answer, and
config.Config and config.FromEnvironment become config.WAF and
config.WAFFromEnvironment. Go fields, test names and prose follow. No
aliases; nothing reads the old names.

Model: opus-5-5

internal/bans/bans_test.go

@@ -101,7 +101,7 @@ func TestFirstBanLongerThanTheMaximumIsPermanent(t *testing.T) {
 	t.Parallel()
 
 	params := defaultParams()
-	params.LimitBanDuration = params.MaxBanDuration + time.Hour
+	params.LimitBanDuration = params.LimitBanPermanentAbove + time.Hour
 	ledger := bans.New(params)
 
 	ban, _ := ledger.BanForLimit(
@@ -121,7 +121,7 @@ func TestLongestBanSetFarOffDoesNotOverflow(t *testing.T) {
 	// hours, is within the maximum, and three times as long would not fit
 	// in a time.Duration. The 15th is permanent.
 	params := defaultParams()
-	params.MaxBanDuration = 100000 * day
+	params.LimitBanPermanentAbove = 100000 * day
 	ledger := bans.New(params)
 	netblock := netip.MustParsePrefix("203.0.113.9/32")
 	now := midnight()
@@ -650,11 +650,11 @@ func TestLookupFillsTheNotesOfTheNetblocksBansWithoutOne(t *testing.T) {
 // defaultParams are the params at the settings' defaults.
 func defaultParams() bans.Params {
 	return bans.Params{
-		LimitBanDuration:     time.Hour,
-		LimitBanRepeatWindow: day,
-		MaxBanDuration:       7 * day,
-		AttackBanDuration:    7 * day,
-		MaxBans:              5000,
+		LimitBanDuration:       time.Hour,
+		LimitBanRepeatWindow:   day,
+		LimitBanPermanentAbove: 7 * day,
+		AttackBanDuration:      7 * day,
+		MaxBans:                5000,
 	}
 }