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/loaders/Sale_Fees.csv

@@ -0,0 +1,33 @@
+contract_number,contract_ref,line_sequence,product,supplier,currency,p_r,mode,price,unit
+1990,24998,1,Commission,SUMITOMO CORPORATION INDONESIA (SSRI),USD,PAY,Per qt,0.5,MT
+1990,24998,1,LC Fees,UBS SWITZERLAND AG,USD,PAY,Per qt,0.25,MT
+2010,25019A,1,Commission,SUMITOMO AUSTRALIA,USD,PAY,Per qt,0.7,MT
+2011,25022A,1,Commission,SUMITOMO CORPORATION INDIA PVT LTD,USD,PAY,Per qt,0.75,MT
+2023,25006,1,LC Fees,UBS SWITZERLAND AG,USD,PAY,Per qt,0.35,MT
+2023,25006,1,Insurance,Marsh / Navigators Insurance Company,USD,PAY,Per qt,0.05,MT
+2024,25002B,1,Commission,SUMITOMO CORPORATION INDIA PVT LTD,USD,PAY,Per qt,0.75,MT
+2024,25002B,1,LC Fees,UBS SWITZERLAND AG,USD,PAY,Per qt,0.25,MT
+2025,25011B,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2026,25011C,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2035,25020B,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2042,25009,1,Commission,SUMITOMO CORPORATION INDONESIA (SSRI),USD,PAY,Per qt,0.49,MT
+2042,25009,1,LC Fees,UBS SWITZERLAND AG,USD,PAY,Per qt,0.35,MT
+2055,25012,1,Finance,TBD Supplier,USD,PAY,Per qt,0.3,MT
+2056,25026C,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2074,25026A,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2075,25020C,1,Finance,TBD Supplier,USD,PAY,Per qt,0.25,MT
+2079,BHP Q3 2026 contract,1,Other,TBD Supplier,USD,PAY,Per qt,1,MT
+2080,BHP Q4 2026 contract,1,Other,TBD Supplier,USD,PAY,Per qt,1,MT
+2092,25028B,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2102,Las Cenizas / Franke 2H 2026 contract,1,Finance,TBD Supplier,USD,PAY,Per qt,0.15,MT
+2103,Las Cenizas / Franke 2H 2026 contract,1,Finance,TBD Supplier,USD,PAY,Per qt,0.15,MT
+2104,Las Cenizas / Franke 2H 2026 contract,1,Finance,TBD Supplier,USD,PAY,Per qt,0.15,MT
+2121,Grace (MDL) spot contract 2026,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2152,25020E,1,Finance,TBD Supplier,USD,PAY,Per qt,0.25,MT
+2154,25022BC,1,Commission,TBD Supplier,USD,PAY,Per qt,0.75,MT
+2163,25026B,1,Finance,TBD Supplier,USD,PAY,Per qt,0.15,MT
+2164,25027,1,Finance,TBD Supplier,USD,PAY,Per qt,0.15,MT
+2165,25028C,1,Finance,TBD Supplier,USD,PAY,Per qt,0.2,MT
+2168,Cosaych 2026 contract,1,Finance,TBD Supplier,USD,PAY,Per qt,0.15,MT
+2170,PPC FD MAY TO INDIA,1,Commission,SUMITOMO CORPORATION INDIA PVT LTD,USD,PAY,Per qt,0.75,MT
+2170,PPC FD MAY TO INDIA,1,LC Fees,UBS SWITZERLAND AG,USD,PAY,Per qt,0.5,MT