chore: Improve logic regarding fast objects

[liuxingbaoyu]

Q	A
Fixed Issues?	Fixes #1, Fixes #2
Patch: Bug Fix?
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

https://github.com/babel/babel/pull/16918#issuecomment-2424613945 Make sure options is a fast object in Babel 7, and make VISITOR_KEYS a slow object.

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/58156