Fix: Refine COLUMN_MAP to avoid duplicate customer_id labels

modules/etl.py

@@ -6,32 +6,26 @@ COLUMN_MAP = {
     # transaction_id variants
     "tx_id": "transaction_id",
     "txn_id": "transaction_id",
-    "trans_id": "transaction_id",
-    "id": "transaction_id",
 
-    # customer_id variants
-    "sender_account_id": "customer_id",
-    "receiver_account_id": "customer_id",
+    # customer_id — ONLY map sender, not receiver
+    "sender_account_id": "customer_id",   # ← sender is the customer
     "account_id": "customer_id",
     "cust_id": "customer_id",
-    "user_id": "customer_id",
+
+    # Keep receiver separate — DO NOT map to customer_id
+    # "receiver_account_id" stays as receiver_account_id
 
     # amount variants
     "tx_amount": "amount",
     "txn_amount": "amount",
-    "trans_amount": "amount",
-    "value": "amount",
 
     # timestamp variants
-    "date": "timestamp",
-    "datetime": "timestamp",
     "transaction_date": "timestamp",
     "tx_date": "timestamp",
 
     # transaction_type variants
     "tx_type": "transaction_type",
     "txn_type": "transaction_type",
-    "trans_type": "transaction_type",
     "type": "transaction_type",
 }