`BaseException`(`SystemExit`/`KeyboardInterrupt`) is swallowed and converted to a `TypeError` when extracting struct fields

Bug Description

Opening as a bug, but this might be considered a feature request

First - thank you for such a great library
We're using it to speedup some python in a web service running under gunicorn and hit a case where a SystemExit is swallowed and converted to a TypeError if it happened to be raised inside a field extractor in a struct

I believe this code is acting as a bare except: but IMO should be more like except Exception:
https://github.com/PyO3/pyo3/blob/ae64e57330427e5ef969f4637c59222d25b1d840/src/impl_/frompyobject.rs#L45-L62

This swallows exceptions deriving from BaseException like KeyboardInterrupt (user pressing Ctrl+C) and SystemExit (used by gunicorn to signal worker shutdown - https://github.com/benoitc/gunicorn/blob/a86ea1e4e6c271d1cd1823c7e14490123f9238fe/gunicorn/workers/base.py#L204

Steps to Reproduce

Seems to only happen with nested structs, see full repro here - https://github.com/vpoverennov/pyo3-exceptions-repro/blob/main/src/lib.rs

with a Nested class like this (simulating SystemExit being thrown into an otherwise innocuous getter function)

class Nested:
    @property
    def v(self):
        raise SystemExit(1)

This works fine and SystemExit is raised when calling repro_w

#[derive(FromPyObject, Debug)]
struct Nested {
    v: i32,
}

#[pyfunction]
fn repro_n(b: Nested) -> i32 {
    println!("repro_n: {:?}", b);
    b.v
}

But this converts SystemExit into a TypeError: argument 'a': failed to extract field Wrapper.n

#[derive(FromPyObject, Debug)]
struct Wrapper {
    n: Nested,
}

#[derive(FromPyObject, Debug)]
struct Nested {
    v: i32,
}

#[pyfunction]
fn repro_w(a: Wrapper) -> i32 {
    println!("repro_w: {:?}", a);
    a.n.v
}

Backtrace

Your operating system and version

Windows 10 / MacOS

Your Python version (python --version)

Python 3.10

Your Rust version (rustc --version)

rustc 1.90.0 (1159e78c4 2025-09-14)

Your PyO3 version

0.26.0

How did you install python? Did you use a virtualenv?

not relevant

Additional Info

No response

Start in src/impl_/frompyobject.rs at the field-extraction logic linked in the report, then reproduce the nested Wrapper/Nested example with a property that raises SystemExit. Done means SystemExit and KeyboardInterrupt propagate from nested field extraction instead of being converted into a TypeError.