Is your feature request related to a problem? Please describe.
Ex. I'm always frustrated when autocomplete doesnt work.

Eg:

• touch TAB doesnt work
• ~/pre TAB doesnt work (should expand to ~/prefix
• ninja ins TAB completes to ninja install_manifest.txt, not ninja install
• cd rustd TAB completes to cd rustdoc/, not cd rustdoc, where I can then specify I wanted to go to rustdoc-json, (in rustc src/test dir
• man cla TAB doesn't comlete (zsh shows clang clang++ clang++-12 clang-12 classes.conf)

Describe the solution you'd like

I'd like to be able to deligate to the underlying shell to provide autocompletion.