[DougSO]

What broke

The image build stopped working today with no change in QFw:

error: Failed to build `ibm-platform-services==0.55.2`
  cause: The build backend returned an error
  ModuleNotFoundError: No module named 'pkg_resources'

The same build six days ago resolved ibm-platform-services to 0.66.1, which
is still what the running containers have.

Why

qiskit-ibm-runtime asks for ibm-platform-services>=0.22.6, and
iqm-client==34.0.1 pins requests==2.32.3 exactly. ibm-platform-services
0.77.0, published in the last few days, moved to ibm-cloud-sdk-core>=3.24.4,
which needs requests>=2.32.4. uv states the conflict:

Because ibm-platform-services>=0.77.0 depends on ibm-cloud-sdk-core>=3.24.4
and ibm-cloud-sdk-core>=3.24.4 depends on requests>=2.32.4, we can conclude
that ibm-platform-services>=0.77.0 depends on requests>=2.32.4.
And because iqm-client==34.0.1 depends on requests==2.32.3, we can conclude
that ibm-platform-services>=0.77.0 and iqm-client==34.0.1 are incompatible.

So the resolver walks back down the ibm-platform-services versions, and with
no floor it reaches 0.55.2. That is the one version in the range published as
an sdist only: 0.59.0 and later all ship wheels. Its build imports
pkg_resources without declaring setuptools as a build dependency, so it
fails under uv's isolated build.

The change

A floor that keeps the resolution where it has been all along. With it, the set
resolves to ibm-platform-services==0.66.1, ibm-cloud-sdk-core==3.24.1 and
requests==2.32.3 — the same combination the current image carries. Nothing
else in the 136 resolved packages changes.

I checked the whole resolved set for other sdist-only packages. The only one is
docplex==2.32.264, which the current image already has at that exact version,
so it builds.

This is not caused by the IBM QDMI work in #156: with ibm-qdmi removed from
setup/qdmi-requirements.txt the resolution fails in exactly the same way.

When it can go

Once iqm-client stops pinning requests to a single version. 35.0.0 and
36.0.0 relax it to requests<3,>=2.32.3, which removes the conflict at its
source and would let the newest ibm-platform-services in. That is a
two-major-version bump on the IQM hardware path, so it wants its own
validation rather than riding along with a build fix.