…micalNetwork

Previously, we were relying on `fastapi` to decode the JSON form of the
request, which was not using `gufe.tokenization.JSON_HANDLER.decoder`.
This resulted in `Settings` objects not being turned into `pydantic`
models from `dict` form, which silently worked until now before changes
in `gufe` for 1.0, in which `Protocol` now requires `settings` to be an
actual `Settings` object on init.

Since the "incomplete" network's edges are a subset of the full network,
we need to select transformations from the "incomplete" network. Without
this, there is a small chance that a Transformation is not part of the
incomplete network, which, in our tests we always assume the attached
TaskHub has three available tasks available to claim. Additionally, I've
added a couple more assertions checking these assumptions.