Qrack demo update for PyQrack v2.0.0

[WrathfulSpatula]

Title:
Update to Qrack demo

Summary:
PyQrack v2.x and PennyLane-Qrack v1.x remove a number of "footguns" regarding sub-optimal simulation settings, but this is a breaking API change for downstream users.

Relevant references:
https://github.com/unitaryfoundation/pyqrack/releases/tag/v2.0.0
https://github.com/unitaryfoundation/pennylane-qrack/releases/tag/v1.0.0

Possible Drawbacks:
Breaking API change

Related GitHub Issues:
None

[github-actions]

👋 Hey, looks like you've updated some demos!

🐘 Don't forget to update the dateOfLastModification in the associated metadata files so your changes are reflected in Glass Onion (search and recommendations).

Please hide this comment once the field(s) are updated. Thanks!

[github-actions]

Your preview is ready 🎉!

You can view your changes here

Deployed at: 2026-05-03 17:24:00 UTC

[josh146]

Thanks for making this PR @WrathfulSpatula! Have you confirmed the demo runs all the way through with latest qrack and PL? If so I think we should be good to approve and merge

[WrathfulSpatula]

@josh146 I ran it with everything updated locally before opening the PR. To be sure, I just ran it again now, after I ran the following:

pip3 install --upgrade pyqrack pennylane-qrack pennylane pennylane-catalyst

Everything completed normally. Just remember that this is specifically PyQrack v2 API and PennyLane-Qrack v1 API (whereas we were in v1 and pre-release respectively, before). You should be good-to-go, and thanks for the review!