Oddly my env was borked bc this (apparently missed by `uv`?) sub-dep
wasn't installed and then `stackscope` was silently failing import and
caused the shield-pause test to also fail (since it couldn't match the
expected `log.devx()` on console). The import failure is not very
explanatory due to the `log.warning()`; change it to `.error()` level.
Also, explicitly import `_sync_pause_from_builtin` in
`examples/debugging/restore_builtin_breakpoint.py` to ensure the ref is
exported properly from `.devx.debug` (which it wasn't during dev of the
prior commit Bp).
In the `examples/debugging/restore_builtin_breakpoint.py` i had put the
pattern-comment lines on the line following the `breakpoint()` bc it
seems that's where `pdb` would always "stop" and print the line to
console? So the test would only pass by actually ensuring that in the
`pexpect` capture..
Now on 3.13 it seems that the `pdb` line halting must have been fixed;
it now renders to console the same `breakpoint()` line?
Anyway it works as you'd expect now but **only** on 3.13 so after this
change we might have to adjust the tests to `pytest.xfail()` on earlier
versions.
Previously we were leaking our (pdb++) override into the Python runtime
which would always result in a runtime error whenever `breakpoint()` is
called outside our runtime; after exit of the root actor . This
explicitly restores any previous hook override (detected during startup)
or deletes the hook and restores the environment if none existed prior.
Also adds a new WIP debugging example script to ensure breakpointing
works as normal after runtime close; this will be added to the test
suite.
Tyler Goodlet