Hidden extra cost adders not reflected in visible proposal line items
When extra cost adders are set to "Public without cost showing" or "Private," their values are included in the Total System Cost but not reflected in any visible line item on the proposal, causing the line items to not add up to the total. This is particularly problematic for adders calculated as "% of storage price," which are not absorbed into the Battery Cost or any other visible line, unlike other adder types (such as $, $/watt, or % of solar cost) that correctly roll into the Solar Cost line. The expected behavior is that hidden "% of storage price" adders should be included in the Battery Cost line, and for battery-only designs all hidden adders should be absorbed into the Battery Cost line, so that visible line items always reconcile to the Total System Cost.