Add Dynamic QFT benchmark

[kris70lesgo]

Description

Adds a dynamic_qft benchmark implementing the semiclassical Dynamic QFT with mid-circuit measurements and classical feed-forward. The circuit mirrors the regular QFT operation order while replacing controlled phase gates from already measured qubits with classically controlled phase rotations.

Fixes #798

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.
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• 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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Verification

• uv run pytest tests/test_bench.py -k dynamic_qft -vv
• uv run pytest
• uvx nox -s lint

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Codecov Report

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[kris70lesgo]

@flowerthrower can u review the pr ?
This PR adds dynamic_qft with a compact implementation that follows the decomposed regular qft benchmark order directly
this version applies feed-forward phase corrections from already measured higher-index qubits before the next Hadamard, so the dynamic circuit mirrors QFT’s operation order more closely. It also uses the expected q/c register names, reversed classical output mapping to account for QFT swaps, no unnecessary helper functions, and no qubit-count cap.