`mypy-status` is not very useful if it triggers `-x`/`--exitfirst`

Reproduce the failure with pytest -s -vvv --mypy, focusing on tests/__init__.py::mypy-status, and compare it with mypy tests/__init__.py. Trace how the plugin reports mypy's status when pytest uses -x/--exitfirst; done means the status test no longer reports errors when the direct mypy check succeeds.

The mypy plugin here falls over, complains about errors, but there aren't any…

% pytest -s -vvv --mypy
===================================== test session starts =====================================
platform linux -- Python 3.13.3, pytest-8.3.5, pluggy-1.5.0 -- /home/madduck/code/tc/tptools/.direnv/python-3.13.3/bin/python3
cachedir: .pytest_cache
rootdir: /home/madduck/code/tc/tptools
configfile: pyproject.toml
testpaths: tests, integration
plugins: anyio-4.9.0, cov-6.1.1, devtools-0.12.2, asyncio-0.26.0, subtests-0.14.1, mypy-1.0.1
asyncio: mode=Mode.STRICT, asyncio_default_fixture_loop_scope=function, asyncio_default_test_loop_scope=function
collected 352 items

tests/__init__.py::mypy PASSED
tests/__init__.py::mypy-status FAILED

========================================== FAILURES ===========================================
________________________________________ test session _________________________________________
mypy exited with status 1.
-------------------------------------- Captured log call --------------------------------------
filelock DEBUG Attempting to acquire lock 140525569634576 on /home/madduck/.tmp/tmpw90y_v42.lock
filelock DEBUG Lock 140525569634576 acquired on /home/madduck/.tmp/tmpw90y_v42.lock
filelock DEBUG Attempting to release lock 140525569634576 on /home/madduck/.tmp/tmpw90y_v42.lock
filelock DEBUG Lock 140525569634576 released on /home/madduck/.tmp/tmpw90y_v42.lock
============================================ mypy =============================================
Found 4 errors in 1 file (checked 27 source files)
=================================== short test summary info ===================================
FAILED tests/__init__.py::mypy-status
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! stopping after 1 failures !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
================================= 1 failed, 1 passed in 0.81s =================================

However:

% mypy tests/__init__.py
Success: no issues found in 1 source file
% echo $?
0