Fixed index performance regression

[Hydrocharged]

I've left a fairly detailed comment for the future, but it doesn't quite explain the exact issue here. It's more so to prevent making a change that would lead to the issue again.

In a nutshell, we were always adding boolean literal expressions in our start and stop expressions, which define the start and stop positions for the underlying tuple iterator. With the Dolt change to fix a case of incorrect results, we were met with even worse results in some circumstances. With the original logic, these literals were harmless to include in multi-expression ranges, but they fundamentally changed the behavior of the stop position with the new logic. They're required to be there though if there are no other expressions, hence it made sense to just always include them. The behavioral change isn't obvious at first glance, hence the need for the long comment (which should make it appear relatively obvious after reading).

This also makes use of QuickFunction where possible, which should always be true for tuple-level filtering, and should provide a small speedup in those cases.

[github-actions]

	Main	PR
covering_index_scan_postgres	343.59/s	348.63/s	+1.4%
index_join_postgres	153.39/s	153.66/s	+0.1%
index_join_scan_postgres	184.11/s	185.15/s	+0.5%
index_scan_postgres	12.57/s	12.93/s	+2.8%
oltp_point_select	2665.37/s	2677.55/s	+0.4%
oltp_read_only	715.40/s	${\color{lightgreen}1860.40/s}$	${\color{lightgreen}+160.0\%}$
select_random_points	114.97/s	115.10/s	+0.1%
select_random_ranges	8.55/s	${\color{lightgreen}133.23/s}$	${\color{lightgreen}+1458.2\%}$
table_scan_postgres	12.00/s	12.28/s	+2.3%
types_table_scan_postgres	5.60/s	5.66/s	+1.0%

[github-actions]

	Main	PR
Total	42090	42090
Successful	15578	15578
Failures	26512	26512
Partial Successes1	5208	5208

	Main	PR
Successful	37.0112%	37.0112%
Failures	62.9888%	62.9888%

Footnotes

1. These are tests that we're marking as Successful, however they do not match the expected output in some way. This is due to small differences, such as different wording on the error messages, or the column names being incorrect while the data itself is correct. ↩

[zachmu]

LGTM, just the one comment