state management

[dfa1]

Problem The intent is to try to unify:

• changes to the PATH
• pushd/popd to save/restore directories
• .envfiles to save/restore variables In hosh everything is stored inside a State object, that is injected to every command to provide current working directory, variables, etc.

Solution Let's take inspiration by nushell for enter/leave and p/n.

Benefit Still unclear to me.

[dfa1]

probably should be designed together with #264

[dfa1]

and with #273