addtotals command - Data Types of fields needed

[tombonfert]

The addtotals command computes the arithmetic sum of all numeric fields for each search result.

Currently, we are not able to determine the numeric fields for a given table. The reason for this is that we are creating an unresolved logical plan, for which the data type of unresolved attributes cannot be determined. There are also other commands where the data types of fields are needed (e.g. streamstats, eventstats)

@nfx @VincentTNR Any ideas on this?