Fix base parts not generating

internal/topdata/parts_discovery.go

@@ -474,7 +474,9 @@ func normalizePartsRowsACBonus(collected []nativeCollectedDataset, cfg project.P
 				}
 			}
 			rowID, ok := cloned["id"].(int)
-			if ok {
+			if isUnsetPartValue(cloned["ACBONUS"]) {
+				cloned["COSTMODIFIER"] = nullValue
+			} else if ok {
 				if value, configured := configuredPartsRowsACBonusValue(rowID, dataset.Dataset.Name, cfg); configured {
 					cloned["ACBONUS"] = value
 				}
@@ -663,15 +665,7 @@ func augmentWithAutogeneratedPartsWithConfig(collected []nativeCollectedDataset,
 
 		// Add rows for discovered IDs that don't already exist.
 		newRows := make([]map[string]any, 0, len(dataset.Rows))
-		for _, row := range dataset.Rows {
-			rowID, ok := row["id"].(int)
-			if cfg.NullUndiscoveredRows && ok {
-				if _, discovered := ids[rowID]; !discovered {
-					continue
-				}
-			}
-			newRows = append(newRows, row)
-		}
+		newRows = append(newRows, dataset.Rows...)
 
 		for rowID := range ids {
 			if row, exists := existingRows[rowID]; exists {