feat: add LittleBigDict and use it in BasicSymbolic

[AayushSabharwal]

No description provided.

[github-actions]

Benchmark Results

	master	7ae8dd5...	master/7ae8dd50bac5d1...
overhead/acrule/a+2	1.11 ± 0.49 μs	1.17 ± 0.48 μs	0.946
overhead/acrule/a+2+b	1.24 ± 0.4 μs	1.23 ± 0.42 μs	1.01
overhead/acrule/a+b	0.306 ± 0.045 μs	0.299 ± 0.11 μs	1.02
overhead/acrule/noop:Int	1.56 ± 0.01 ns	1.56 ± 0.01 ns	1
overhead/acrule/noop:Sym	0.0513 ± 0.0063 μs	0.0411 ± 0.0019 μs	1.25
overhead/rule/noop:Int	0.0364 ± 0.026 μs	0.0591 ± 0.026 μs	0.615
overhead/rule/noop:Sym	0.0559 ± 0.0055 μs	0.0561 ± 0.01 μs	0.995
overhead/rule/noop:Term	0.0555 ± 0.011 μs	0.0569 ± 0.061 μs	0.976
overhead/ruleset/noop:Int	0.122 ± 0.011 μs	0.121 ± 0.034 μs	1.01
overhead/ruleset/noop:Sym	0.147 ± 0.0052 μs	0.146 ± 0.0067 μs	1.01
overhead/ruleset/noop:Term	5.48 ± 1.4 μs	10.8 ± 2.9 μs	0.505
overhead/simplify/noop:Int	0.227 ± 0.033 μs	0.258 ± 0.034 μs	0.878
overhead/simplify/noop:Sym	0.231 ± 0.018 μs	0.233 ± 0.024 μs	0.988
overhead/simplify/noop:Term	0.0519 ± 0.01 ms	0.0579 ± 0.012 ms	0.897
overhead/simplify/randterm (+, *):serial	0.124 ± 0.0049 s	0.161 ± 0.016 s	0.767
overhead/simplify/randterm (+, *):thread	0.0711 ± 0.0089 s	0.0856 ± 0.017 s	0.83
overhead/simplify/randterm (/, *):serial	0.236 ± 0.048 ms	0.288 ± 0.031 ms	0.821
overhead/simplify/randterm (/, *):thread	0.269 ± 0.025 ms	0.325 ± 0.026 ms	0.829
overhead/substitute/a	0.112 ± 0.018 ms	0.227 ± 0.02 ms	0.495
overhead/substitute/a,b	0.1 ± 0.015 ms	0.155 ± 0.022 ms	0.646
overhead/substitute/a,b,c	21.3 ± 2.5 μs	21.9 ± 1 μs	0.974
polyform/easy_iszero	0.0575 ± 0.011 ms	0.102 ± 0.034 ms	0.561
polyform/isone	3.1 ± 0.01 ns	3.1 ± 0.01 ns	1
polyform/iszero	1.7 ± 0.085 ms	4.66 ± 0.95 ms	0.365
polyform/simplify_fractions	2.34 ± 0.15 ms	5.48 ± 0.42 ms	0.427
time_to_load	1.03 ± 0.0066 s	1.05 ± 0.027 s	0.983

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).