Implemented Rollback Functionality

.env.example

@@ -6,6 +6,12 @@ SHOPIFY_ACCESS_TOKEN=your-admin-api-access-token
 TARGET_TAG=sale
 PRICE_ADJUSTMENT_PERCENTAGE=10
 
+# Operation Mode Configuration
+# OPERATION_MODE determines whether to update prices or rollback to compare-at prices
+# Options: "update" (default) or "rollback"
+OPERATION_MODE=update
+
 # Optional Configuration
 # PRICE_ADJUSTMENT_PERCENTAGE can be positive (increase) or negative (decrease)
-# Example: 10 = 10% increase, -15 = 15% decrease
+# Example: 10 = 10% increase, -15 = 15% decrease
+# Note: PRICE_ADJUSTMENT_PERCENTAGE is only used in "update" mode