Fast expression parse

[ggmichaelgo]

Faster Expression Parser!

Here are the performance improvements by using Expression2
|Expression Type|Performance Improvement|

Expression Type	Baseline (iter/s)	Optimized (iter/s)	Improvement (%)
String	1,585,127.3	1,775,098.1	12.0%
Literal	478,033.9	1,392,155	191.2%
Variable	172,837.7	183,022.3	5.9%
Number	150,488.8	179,076.9	19.0%
Range	58,494.9	67,537.9	15.5%
All	28,498.2	32,861.4	15.3%

Benchmark Improvement

main branch (baseline)

ruby 3.4.0dev (2024-04-23T16:59:11Z v3.4.0-pshopify-pr.. 70b931820e) +YJIT [arm64-darwin23]
Warming up --------------------------------------
              parse:    14.000 i/100ms
             render:    70.000 i/100ms
     parse & render:    11.000 i/100ms
Calculating -------------------------------------
              parse:    143.139 (± 0.0%) i/s    (6.99 ms/i) -      1.442k in  10.074118s
             render:    707.161 (± 0.6%) i/s    (1.41 ms/i) -      7.140k in  10.097056s
     parse & render:    115.156 (± 0.9%) i/s    (8.68 ms/i) -      1.155k in  10.031652s

fast-expression-parse branch

ruby 3.4.0dev (2024-04-23T16:59:11Z v3.4.0-pshopify-pr.. 70b931820e) +YJIT [arm64-darwin23]
Warming up --------------------------------------
              parse:    14.000 i/100ms
             render:    70.000 i/100ms
     parse & render:    11.000 i/100ms
Calculating -------------------------------------
              parse:    145.446 (± 0.7%) i/s    (6.88 ms/i) -      1.456k in  10.010856s
             render:    708.090 (± 0.4%) i/s    (1.41 ms/i) -      7.140k in  10.083630s
     parse & render:    116.499 (± 0.9%) i/s    (8.58 ms/i) -      1.166k in  10.008950s

We see a very small ~1.6% performance boost...
However, with real themes, we will definitely see performance improvements.