chore(cap): raise per-order spend cap default from 200 to 500 (#39)

pkg/config/config.go

@@ -137,11 +137,13 @@ func getEnvOrDefault(key, defaultValue string) string {
 	return defaultValue
 }
 
-// loadMaxOrderCents reads MAX_ORDER_CENTS. Default $200. Explicit 0 disables
-// the cap. Garbage or negative values fall back to the default with a warning
-// so an operator typo cannot silently disable a fraud control.
+// loadMaxOrderCents reads MAX_ORDER_CENTS. Default $500 — aligns with the
+// PSD2 TRA exemption ceiling (above this, Stripe always requests SCA, so the
+// cap is only meaningful below it). Explicit 0 disables the cap. Garbage or
+// negative values fall back to the default with a warning so an operator
+// typo cannot silently disable a fraud control.
 func loadMaxOrderCents() int {
-	const defaultCap = 20000
+	const defaultCap = 50000
 	raw := os.Getenv("MAX_ORDER_CENTS")
 	if raw == "" {
 		return defaultCap

pkg/config/config_test.go

@@ -24,12 +24,12 @@ func TestLoadMaxOrderCents(t *testing.T) {
 		env  string // "" means unset
 		want int
 	}{
-		{"empty falls back to default", "", 20000},
+		{"empty falls back to default", "", 50000},
 		{"explicit zero disables", "0", 0},
-		{"valid override", "50000", 50000},
-		{"negative falls back to default", "-1", 20000},
-		{"garbage falls back to default", "two hundred", 20000},
-		{"empty after trim falls back to default", "", 20000},
+		{"valid override", "30000", 30000},
+		{"negative falls back to default", "-1", 50000},
+		{"garbage falls back to default", "two hundred", 50000},
+		{"empty after trim falls back to default", "", 50000},
 	}
 
 	for _, tc := range cases {