MeTTa definitions of stdlib don't work in modules imported by import! function

[vsbogd]

Code which uses MeTTa definitions of stdlib inside a module imported using import! doesn't work:

Steps to reproduce imported.metta:

!(if True (println! imported-ok) (println! imported-nok))

import.metta:

!(import! &m imported.metta)

!(if True (println! self-ok) (println! self-nok))

Run import.metta

Expected result

metta import.metta
imported-ok
self-ok
[()]
[()]

Actual result

imported-ok
imported-nok
self-ok
[()]
[()]

Root cause Metta::new_loading_runner creates an empty space but doesn't import stdlib into it while it gets all standard tokens. Thus all MeTTa definitions of the stdlib are not available for the interpreted code. It affects minimal MeTTa even more serious because interpreter itself is also part of the MeTTa stdlib code.

https://github.com/trueagi-io/hyperon-experimental/blob/0c17c629dce868a3d954c2ff725e7586ac4c8a8b/lib/src/metta/runner/mod.rs#L151-L164

This should be fixed during work on https://github.com/trueagi-io/hyperon-experimental/issues/470

[vsbogd]

It is a blocker for minimal MeTTa work.

[vsbogd]

Fixed in #574