🐛 Cap PennyLane version

[flowerthrower]

Description

This PR caps the PennyLane version to <0.45

The reason for this change is that CI started failing with pennylane-catalyst==0.14.1, which allows pennylane>=0.44.1 without an upper bound. Fresh builds can therefore resolve pennylane==0.45.0, but Catalyst 0.14.1 still imports pennylane.transforms.core.transform_dispatcher, which was removed in PennyLane 0.45.

This change adds an explicit pennylane<0.45 constraint.

Assisted-by: GPT-5.5 via Codex

Checklist

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
• I have added entries to the changelog for any noteworthy additions, changes, fixes, or removals.
• I have added migration instructions to the upgrade guide (if needed).
• The changes follow the project's style guidelines and introduce no new warnings.
• The changes are fully tested and pass the CI checks.
• I have reviewed my own code changes.

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[flowerthrower]

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[coderabbitai]

✅ Actions performed

Full review triggered.

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 4c0e3873-c4c6-4086-a4a7-23d50cc86765

📥 Commits

Reviewing files that changed from the base of the PR and between 6652b98 and 7a538b1.

⛔ Files ignored due to path filters (1)

• uv.lock is excluded by !**/*.lock

📒 Files selected for processing (3)

• .github/workflows/ci.yml
• CHANGELOG.md
• pyproject.toml

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📝 Walkthrough

Summary by CodeRabbit

Chores

• Dependencies – Updated PennyLane version constraints to remain below 0.45 for compatibility with Catalyst v0.14.1.

Walkthrough

This PR pins PennyLane to versions <0.45 to ensure compatibility with Catalyst v0.14.1. The upper-bound constraint is added to three dependency sections in pyproject.toml, documented in the changelog, and reflected in the CI workflow by explicitly installing PennyLane 0.44.1 for cpp-linting.

Changes

PennyLane Compatibility Pinning for Catalyst v0.14.1

Layer / File(s)	Summary
Dependency version constraints in pyproject.toml pyproject.toml	Upper-bound constraint pennylane<0.45 added to build-system requires, project dependencies, and the build dependency group to ensure compatibility with Catalyst v0.14.1.
Changelog entry and CI workflow update CHANGELOG.md, .github/workflows/ci.yml	Changelog documents the PennyLane version pin, and the cpp-linter CI job is updated to install both pennylane-catalyst==0.14.1 and pennylane==0.44.1.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Poem

🐰 A pin for PennyLane, bright and clear,
With Catalyst bound for a compatible year,
Build, deps, and docs all agree,
Version harmony—0.45 we'll never see! ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely summarizes the main change: capping the PennyLane version constraint to prevent CI breakage with incompatible versions.
Description check	✅ Passed	The PR description includes a clear summary of the change, the rationale for the constraint, and relevant technical details about the PennyLane version incompatibility.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch cap-pennylane-version

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[burgholzer]

I think it would be slightly cleaner to also provide a lower bound for the pennylane dependency here. Most likely, pennylane~=0.44.0 (or pennylane~=0.44.1) is the right thing here.
Otherwise this LGTM

[burgholzer]

Thanks, LGTM!