but

backend/internal/config/config.go

@@ -94,6 +94,19 @@ func (c *Config) DSN() string {
 	)
 }
 
+// TierForPriceID maps a Stripe price ID back to the corresponding
+// subscription tier. Returns empty string if the price is unrecognised.
+func (c *Config) TierForPriceID(priceID string) string {
+	switch priceID {
+	case c.StripePriceIDPremium:
+		return "premium"
+	case c.StripePriceIDPro:
+		return "pro"
+	default:
+		return ""
+	}
+}
+
 func getEnv(key, fallback string) string {
 	if v := os.Getenv(key); v != "" {
 		return v