GeezerVison

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@crates/capi/src/abstract_/number.rs`:
- Around line 33-86: The tests currently exercise Python-level methods but not
the exported C-ABI functions, so add unit tests that call the no_mangle extern
"C" symbols directly (PyNumber_Add, PyNumber_Lshift, PyNumber_Or,
PyNumber_Rshift, PyNumber_Subtract and PyNumber_Index) via the pyo3 ffi
pointers; inside Python::with_gil (or Python::attach) obtain raw PyObject
pointers for lhs/rhs, call the corresponding pyo3::ffi::PyNumber_* function in
an unsafe block, check the returned *mut pyo3::ffi::PyObject is non-null, wrap
or convert it back to a PyObject and extract the i64/expected value, and DECREF
returned objects as appropriate to avoid leaks so these tests truly validate the
exported C-ABI entrypoints.
- Around line 3-31: The FFI entry points PyNumber_Add, PyNumber_Index,
PyNumber_Lshift, PyNumber_Or, PyNumber_Rshift, and PyNumber_Subtract perform raw
pointer derefs and must be declared unsafe; update each function signature from
the current extern "C" form to be pub unsafe extern "C" fn while preserving the
no_mangle attribute (or replacing #[no_mangle] if present) so the functions are
exported with the correct caller safety contract (adjust signatures for
PyNumber_Add, PyNumber_Index, PyNumber_Lshift, PyNumber_Or, PyNumber_Rshift,
PyNumber_Subtract).

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@crates/capi/src/abstract_/number.rs`:
- Around line 33-34: The test module is permanently disabled by #[cfg(false]);
change it to #[cfg(test)] so tests are compiled and run, then update the tests
in mod tests to exercise the C ABI entrypoints for the new PyNumber_* functions
(call the exported FFI wrappers rather than internal helpers) and adjust any
signatures/unsafe blocks to match the C-ABI bindings (e.g., use the public
extern "C" functions named PyNumber_*) so the tests actually invoke the FFI
layer; alternatively, if you intend to defer tests, remove the dead mod tests
block entirely.