fix: decompose BlueprintCircuits before re-parametrization to fix QPY…

[92meharali]

… UUID mismatch (#1042)

When a BlueprintCircuit (e.g. ZZFeatureMap) is passed to ComputeUncompute, its internal gate-level symbolic expressions may use the original parameter UUIDs from the blueprint's own ParameterView even after assign_parameters() is called on the outer circuit. This is because BlueprintCircuits use lazy evaluation via _build(), so the gate-level expressions are not fully materialized until the circuit is iterated or decomposed.

When IBM Runtime serializes the SamplerV2 PUB via QPY for remote execution on real hardware, the expression tree on the backend contains the original blueprint UUID while the BindingsArray keys hold the new re-parametrized UUID, causing:

QpyError: Cannot bind following parameters not present in expression:
{Symbol { name: "x", uuid: ..., index: Some(0), vector: Some(...) }}

Fix: call circuit.decompose() on both input circuits before assigning the new ParameterVectors. This forces full materialization of the circuit's gate-level instructions so that all parameter UUID references are consistent before re-parametrization, QPY serialization, and binding.

Fixes: #1042

Summary

• Decompose BlueprintCircuits (e.g. ZZFeatureMap) before re-parametrization in BaseStateFidelity._construct_circuits
• Fixes QpyError: Cannot bind following parameters not present in expression when using ComputeUncompute + SamplerV2 on IBM Runtime
• Adds regression test and release note

Fixes #1042

Test plan

• pytest test/state_fidelities/test_compute_uncompute.py
• CI green on PR
• (Optional) Reproduce original issue on IBM hardware with ZZFeatureMap + PegasosQSVC

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