Add scripts for importing prices and sale contract fees; update purchase fees script

- Implemented `import_prices.py` to import price index values from a CSV file with migration mapping.
- Created `import_sale_fees.py` for importing sale contract line fees, including detailed logging and error handling.
- Modified `import_purchase_fees.py` to change fee type from 'ordered' to 'budgeted' and added fee ID logging.

Reference Data/python_project/helpers/tryton_helpers.py

@@ -510,10 +510,17 @@ def find_sale_contract_by_number(contract_number):
     
     Sale = Model.get('sale.sale')
     
-    # Search by number and party fields
+    # Search by number
     contracts = Sale.find([
         ('number', '=', contract_number.strip())
     ])
+
+    # If not found, try by adding "S-" prefix (if not already present)
+    if not contracts and not contract_number.strip().startswith('S-'):
+        prefixed_number = f"S-{contract_number.strip()}"
+        contracts = Sale.find([
+            ('number', '=', prefixed_number)
+        ])
     
     if contracts:
         return contracts[0]