Avoid some allocations in BitVector256

[xtqqczze]

Avoid eight unnecessary allocations (the list, plus seven internal arrays due to resizing).

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[MihaZupan]

These methods are only called by the debugger when you hover over a SearchValues instance, so the allocation doesn't matter here.

[xtqqczze]

These methods are only called by the debugger when you hover over a SearchValues instance, so the allocation doesn't matter here.

Maybe it's of lesser importance, but it's still eight unnecessary allocations (the list and seven internal arrays).