fix: Add shares input prompt for sell order in trading journal

src/trading/journal.py

@@ -545,6 +545,10 @@ def journal_menu():
                 continue
                 
             if direction == "2":  # Sell order
+                shares = get_user_input("Enter number of shares to sell:", int)
+                if shares is None:
+                    continue
+                    
                 exit_price = get_user_input("Enter exit price:", float)
                 if exit_price is None:
                     continue