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.

ITSA.code-workspace

@@ -0,0 +1,9 @@
+{
+	"folders": [
+		{
+			"path": "."
+		}
+	],
+	"settings": {
+	}
+}