Should MAXSCOREBulkScorer sometimes apply filters after essential clauses.

Currently, MAXSCOREBulkScorer always applies filters in parallel with essential clauses (by intersecting the filter with a heap containing essential clauses in a leap frog fashion).

When the sum of costs of essential clauses is less than the cost of the filter, it would likely be more efficient to "post filter" hits of essential clauses, ie. pull hits of essential clauses into a `DocAndScoreBuffer` and then remove hits from this buffer that don't match the filter.

Start in MAXSCOREBulkScorer and trace how essential clauses and filters are intersected, including the DocAndScoreBuffer path. Compare the costs of essential clauses with the filter and determine how the post-filtering branch should preserve matching and scoring behavior. Done means the cheaper execution strategy is selected under the stated condition and focused coverage verifies both paths.

Written by the indexing model from the issue text.