✨ Add Constant Propagation

[LiRem101]

Description

This PR introduces the optimization pass constant propagation. It propagates the state of a quantum machine through a circuit and optimizes the applied gates with respect to the current state. Namely, it removes controlling qubits, exchanges controlling qubits with controlling classical values and removes phase gates which only introduce a global phase. The optimization routine is based on this paper, accepted at QSW 2026.

I suggest having constant propagation switched to off on default, because it assumes that all states are initial zero, can take quite a while and can create dynamic circuits, which might not be everyone's goal.

GPT-4 and GPT-5 have been used for refactoring and for first drafts of code. No Gen AI was integrated in the used IDE.

Fixes #(1387)

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.
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