Focus on improving speed. Refactor out common code for reuse among multiple collector implementations.

Include a high-speed generational garbage collector as an alternative to the simple collector. It's intended for heavy-duty use like DuckLogic's VM. This will be a global collector, which only has one instance.

Possibly providing an "arena" collector a single-threaded alternative to the "simple" collector. It would only allow a single context to be created and wouldn't be thread safety. This provides a simple alternative to typed-arena andbumpalo (which are only single-threaded). Adding thread-safety to the simple-collector added significant complexity, which isn't always needed.