feat: cross hints and shorter trainer transitions with a rust solver

[bryanlundberg]

What does this PR do?
Replaces the npm cube-solver with cube-solver-rs, a Rust/WebAssembly solver that shares a new cube-core crate with the TNoodle scrambler.

	Before (npm cube-solver)	After
PLL/ZBLL transition	~20 moves	~13 to 14
OLL transition	~20 moves	~10
COLL transition	~20 moves	~11
F2L transition	~20 moves	~7
Table setup	1.3 s	~114 ms
Hints	yellow only	all six colors in ~3 ms
Transition time	median 18 ms	median 25 to 36 ms

cube-solver also returned non-optimal crosses and xcrosses in 40 of 600 and 174 of 2400 fixture cases; the new solver is never longer.

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• I have reviewed my code and believe it is ready for merging.
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