ArkRegex: A drop in replacement for new RegExp() with types

Yes, there are limits on what string literals can precisely represent, but we've tried to be pragmatic about trade offs around clarity, concision and performance.

Subexpressions like `\\w` or `[a-Z]` would just be inferred as `${string}`, but that doesn't mean the inference won't be useful. For example:

expression: regex("^\\w+@\\w+\\.\\w+$") type: Regex<`${string}@${string}.${string}`>