type of cargoMaxWeight

[kokosabu]

The type of cargoMaxWeight is specified as a string.
This may be more convenient for the recipient to use the number in their calculations.

One advantage of being a string is that it can be used for different units. (For example, "0.5kg", "500g", etc.)
However, it is stated in the description that the unit is kg.

For this reason, we think that number is preferable to string.