Cannot disable CI Session handling in v4.5.1

There is no setting to disable CI4 Session from the beginning.
And now some CI4 features depend on CI4 Session.
If you don't use CI4 Session, these features do not work or cause an error like yours.

The following code in the framework starts CI4 Session.
service('session')
session()

I don't know your app works fine with CI4.3 or 4.5, but if you customize the following,
the error would be gone.
https://github.com/codeigniter4/CodeIgni....php#L1062

> I raised this because the manual seems to suggest that use of CI/Session is optional. 

I'm not sure it is optional or not.
If we add an option to disable CI4 Session, some features that depend on CI4 Session will not work.

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