pythonGH-121089)

Co-authored-by: d.grigonis <dgrigonis@users.noreply.github.com>

pythonGH-121089)

Co-authored-by: d.grigonis <dgrigonis@users.noreply.github.com>

PR #121089 added an eager import for types.MethodType, but
still left the existing hacks for lazily importing from types.

We could also create MethodType internally in functools.py (e.g.,
by using `type(Placeholder.__repr__)`, but it feels not worth it at
this point, so instead I unlazified all the usages of types in the
module.

#2546 is blocked because we don't run the tests on this branch with
Python 3.14, but these are configured as required checks. Since Ops 2.23
only specifies Python `>=3.8`, we'd expect it to run fine with Python
3.14.

In addition to adding 3.14 to the list of versions in CI, we also need
to add it to the list of environments in `tox.ini`, and follow #2091 in
patching some of the tests: we now need to wrap our `functools.partial`
objects in `staticmethod` due to `partial` implementing the decriptor
protocol in Python 3.14
(python/cpython#121027,
python/cpython#121089). However, because we're
on an older `pyright` version in this maintenance branch, this leads to
type checking errors which we ignore (bumping `pyright` resolves this
but introduces 20+ other errors which would add noise to this PR).