:bug: Fix strip idle qubits

[TeWas]

Description

This PR fixes the issue of incorrectly removing idle qubits that are not idle in both circuits. The following changes have been made:

• Previously, idle qubits were removed regardless of their status in both circuits. Now, an idle qubit is removed only if:
  • it is idle in both circuits
  • it is idle in one circuit and does not exist in the other circuit
• To implement this logic, a dedicated method stripIdleQubits has been created in QCEC. This method considers both circuits in conjunction
• The stripIdleQubits method:
  • examines each logical qubit in the initialLayout of the larger circuit
  • checks if the corresponding physical qubit is idle
  • then searches for this logical qubit in the other circuit
  • if the corresponding physical qubit in the other circuit is also idle, then the logical and corresponding physical qubit are removed from each circuit, respectively, under the following conditions:
    • neither the logical nor the physical qubit appears in the output permutation (applies to both circuits)
    • or if the initial and output permutations match for this qubit (applies to both circuits)
  • if an idle logical qubit is present in one circuit only, it is removed, if neither the logical nor the physical qubit appears in the output permutation, or the initial and output permutations match for this qubit

Fixes #372

Checklist:

• [x] The pull request only contains commits that are related to it.
• [x] I have added appropriate tests and documentation.
• [x] I have made sure that all CI jobs on GitHub pass.
• [x] The pull request introduces no new warnings and follows the project's style guidelines.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 97.08738% with 3 lines in your changes are missing coverage. Please review.

Project coverage is 96.4%. Comparing base (cc1d2c3) to head (cd0898e). Report is 1 commits behind head on main.

Additional details and impacted files

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