Fix red develop 5e32e975be6c

The merge lane found `develop` red at `5e32e975be6c6760b028bfda101d8b42c03f5f39` on its own: no queued PR merges until it is fixed. Failing (tests and gate stages): - `python-types-mypy` The whole gate log: artifact `12783` on lane task 11665. Make `develop` pass its full gate again. Open a PR as usual: the merge lane merges a PR that fixes some of these and adds no failure even while `develop` is red.

develop red was a mypy 2.4.0 INTERNAL ERROR (stale incremental cache), not a type error. check_python_lint now drops the cache and reruns mypy cold once on an internal error. Quick gate green; PR #7452 queued to the merge lane.