[WIP] refactor: move to Moshi

[AayushSabharwal]

Currently implemented to be mostly identical to the old ADT. Will add Const and ArrayOp in future PRs to be able to limit the scope of individual PRs.

We don't want to repeat the MTKv10 PR :D

[github-actions]

Benchmark Results

	master	c7fa1e2...	master / c7fa1e2...
overhead/acrule/a+2	0.983 ± 0.25 μs	0.911 ± 0.22 μs	1.08 ± 0.38
overhead/acrule/a+2+b	0.976 ± 0.27 μs	1.07 ± 0.21 μs	0.916 ± 0.31
overhead/acrule/a+b	0.271 ± 0.027 μs	0.219 ± 0.071 μs	1.23 ± 0.42
overhead/acrule/noop:Int	1.56 ± 0.92 ns	1.55 ± 0.01 ns	1.01 ± 0.59
overhead/acrule/noop:Sym	22.1 ± 6.7 ns	22 ± 6 ns	1.01 ± 0.41
overhead/get_degrees/large_poly	0.149 ± 0.0081 s	0.0655 ± 0.0057 s	2.28 ± 0.23
overhead/rule/noop:Int	0.0344 ± 0.024 μs	0.0416 ± 0.025 μs	0.826 ± 0.76
overhead/rule/noop:Sym	0.0334 ± 0.025 μs	0.0501 ± 0.025 μs	0.666 ± 0.59
overhead/rule/noop:Term	0.0334 ± 0.025 μs	0.0501 ± 0.024 μs	0.667 ± 0.59
overhead/ruleset/noop:Int	0.12 ± 0.012 μs	0.053 ± 0.003 μs	2.28 ± 0.26
overhead/ruleset/noop:Sym	0.129 ± 0.037 μs	0.0538 ± 0.0021 μs	2.4 ± 0.7
overhead/ruleset/noop:Term	5.09 ± 0.74 μs	3.65 ± 0.056 μs	1.39 ± 0.2
overhead/simplify/noop:Int	0.279 ± 0.031 μs	1.56 ± 0.01 ns	179 ± 20
overhead/simplify/noop:Sym	0.266 ± 0.033 μs	0.0507 ± 0.0003 μs	5.24 ± 0.66
overhead/simplify/noop:Term	0.0532 ± 0.0055 ms	15.4 ± 0.44 μs	3.46 ± 0.37
overhead/simplify/randterm (+, *):serial	0.128 ± 0.0087 s	0.0426 ± 0.00074 s	3 ± 0.21
overhead/simplify/randterm (+, *):thread	0.0729 ± 0.0059 s	28.5 ± 9.7 ms	2.55 ± 0.9
overhead/simplify/randterm (/, *):serial	0.263 ± 0.026 ms	0.122 ± 0.02 ms	2.16 ± 0.41
overhead/simplify/randterm (/, *):thread	0.295 ± 0.029 ms	0.133 ± 0.022 ms	2.22 ± 0.42
overhead/substitute/a	0.109 ± 0.011 ms	0.0529 ± 0.0053 ms	2.06 ± 0.3
overhead/substitute/a,b	0.0922 ± 0.0098 ms	0.0512 ± 0.0049 ms	1.8 ± 0.26
overhead/substitute/a,b,c	21.4 ± 2.4 μs	13.9 ± 1.9 μs	1.54 ± 0.27
polyform/easy_iszero	0.0417 ± 0.0063 ms	0.0437 ± 0.00079 ms	0.954 ± 0.14
polyform/isone	3.1 ± 0.01 ns	2.79 ± 0.01 ns	1.11 ± 0.0053
polyform/iszero	1.44 ± 0.03 ms	1.44 ± 0.025 ms	0.999 ± 0.027
polyform/simplify_fractions	1.95 ± 0.11 ms	2.32 ± 0.05 ms	0.84 ± 0.05
time_to_load	1.1 ± 0.0063 s	1.11 ± 0.011 s	0.987 ± 0.012

Benchmark Plots

A plot of the benchmark results have been uploaded as an artifact to the workflow run for this PR.
Go to "Actions"->"Benchmark a pull request"->[the most recent run]->"Artifacts" (at the bottom).

[AayushSabharwal]

The transition is more or less complete. However, we are currently much slower. I'll investigate why.