The `term` and `phrase` suggesters have different options to filter candidates
based on their frequencies. The `popular` mode for instance filters candidate
terms that occur in less docs than the original term. However when we compute this threshold
we use the total term frequency of a term instead of the document frequency. This is not inline
with the actual filtering which is always based on the document frequency. This change fixes
this discrepancy and clarifies the meaning of the different frequencies in use in the suggesters.
It also ensures that the threshold doesn't overflow the maximum allowed value (Integer.MAX_VALUE).
Closes#34282
7b49beb9b0