feat(typescript-estree): use a jump table instead of switch/case for conversion logic

[bradzacher]

PR Checklist

• Addresses an existing open issue: fixes Repo: investigate switching core TS->ESTree conversion logic from a "switch/case" to a "jump table" for performance improvements #6149
• That issue was marked as accepting prs
• Steps in CONTRIBUTING.md were taken

Overview

This PR converts the parser's internal conversion logic from a switch to a jump table.
I tried two different versions of this:

1. direct conversion of the switch to a jump table in the class.
2. conversion of the entire logic from a class to a function, in addition to the jump table conversion

I found the following results:

• Original cumulative AST conversion across our codebase was ~765ms.
• With the changes from (1), conversion time barely moved to ~750ms (~1% reduction).
• With the changes from (2), conversion time moved a bit more to ~685ms (~10% reduction).

I was hoping for a bit more than that, but ultimately that's not a that bad. In the grand scheme of things, however, this is only a ~0.2% reduction in the total lint time for our repo. This is because on our codebase the lint rules themselves take ~70% of the overall lint time - because we use type-aware rules.

TODO:

• finish the class -> functional conversion and fix tests/types.
• try this on a larger repo that doesn't use type-aware rules to see how well it translates to runtime reduction.

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🟥 Failed Commands
Node 18 - nx test typescript-estree
Node 14 - nx test typescript-estree --coverage=false
nx run-many --target=typecheck --all --parallel

✅ Successfully ran 41 targets

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[typescript-eslint]

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[bradzacher]

I spent some time testing and retesting this on the large codebase at canva (~48k files) where they don't use type-aware linting.
Total saved time with this change was less than 300ms (25.22s -> 24.98s).
Total time for a lint run is a little over 6 minutes (362s), so conversion time is ~6% of the lint run. Time saved with this change was 0.06%.

It really is just insignificant - not worth landing this, closing.