feat: Override array methods to avoid proxy creation while iterating and updating (#1184)

* Intercept array methods to skip proxy creation for perf

* Add allReassigned flag

* Improve isArrayIndex

* Drop dead test

* Move array methods to a new plugin

* Run additional base tests with array method plugin enabled

* Add immutability-profiling script

* Update benchmarks to use enableArrayMethods

* Add additional array method tests

* Document array method internal behaviors

* Update import size values

* Update import size command

* Add array plugin docs