This introduces a Python filesystem API on `Transport` that is implemented
entirely with eval/exec provided by the underlying transport subclass.
Updates existing mpremote filesystem commands (and `edit) to use this API.
Also re-implements recursive `cp` to allow arbitrary source / destination.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Signed-off-by: Damien George <damien@micropython.org>