♻️ Consolidate duplicated DD circuit simulation

[burgholzer]

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Goal

Eliminate duplicated circuit-execution logic between Core's dd::Simulation helpers and DDSIM's CircuitSimulator without introducing a cyclic or inverted dependency.

Constraints

• The DDSIM QDMI reference device remains in MQT Core for v4 and requires circuit execution.
• Core currently exposes Python sample, simulate, and simulate_statevector helpers.
• SyReC and QCEC have identified dependencies on parts of the current API.

Work

• Inventory the exact shared execution kernel: unitary application, virtual swaps, measurement sampling, dynamic shots, reset, classical control, RNG, permutations, and garbage handling.
• Decide which minimal primitives stay in Core for the QDMI device and which public simulator API belongs in DDSIM.
• Remove unused virtual-operation helpers where possible.
• Migrate Python and downstream consumers explicitly.

Acceptance criteria

• One implementation owns each execution behavior.
• Core does not depend on DDSIM merely to build its retained QDMI device.
• DDSIM remains the owner of the public simulator abstraction.
• Dynamic circuits, repeated jobs, seeding, output permutations, and Python results retain coverage.