Add "Avg. number of individuals receiving period supplies monthly" to Annual Survey

Summary

Add the Avg. number of individuals receiving period supplies monthly to Annual Survey

Why

NDBN asks for these values from the banks in their annual survey. Much easier if we can calculate it for them

Details

BLOCKED by #4283
Add a field for the average number of individuals receiving period supplies monthly to the Annual survey
Also add a note on the value "This estimate is based on 1 person per kit, and a default of 25 pads/tampons per person for non-kit items."

How do we know the # of individuals receiving period supplies?

• we can assume that there is a 1-1 kit to person ratio, unless there is a value for quantity for individual on the kit item, in which case we should use that value (if it is 2, it is a 2 to 1 kit to person ratio)
• The base items for period supplies have the category "Menstrual Supplies/Items"
• Items have a "distribution quantity" -- which is the number we use when doing individual requests, so that is a reasonable quantity to use.
• What do we do if there is no "distribution quantity", though? We use 25, (per a conversation between CL, Lynn (of the NDBN) and Judi M on Dec 12, 2023
• Sum these values for the year, and then divide by 12 to get the monthly average.

Criteria for completion

[ ] Value is calculated and shown on the report, along with the note.
[] Tests to support this behaviour

Start by reviewing the Annual Survey report and the dependency in issue #4283. Trace how annual period-supply distribution data is represented, including kit quantities and distribution quantities, then add the monthly average and specified note to the report. Add tests covering the calculation and report output.