Move ordering

[dannyhammer]

Relevant link(s):

• https://www.chessprogramming.org/Move_Ordering
• https://www.chessprogramming.org/MVV-LVA
• https://rustic-chess.org/search/ordering/how.html

Start with a simple MVV-LVA implementation. Ensure that we are not sorting the entire list, rather only sorting one element at a time. Refer to Rustic for ideas on building a "move picker"

[dannyhammer]

Re: "sorting one element at a time"

I implemented Rustic's idea of a "move picker" and found the results to be... underwhelming. I'm not even bothering to post bench results because the bench on depth 6 isn't even finishing in a reasonable time. If I just use moves.sort_by_cached_key, however, it works well enough.

Perhaps a "move picker" is an optimization for a later date.

Side note: It looks like Rustic stores move scores in the move itself, which Toad does not do. This may warrant further investigation.