Zero-ancilla partial equivalence checking

[reb-ddm]

Description

Changed isCloseToIdentityRecursive such that it supports garbage qubits and a flag can be added to only check if it's close to a diagonal matrix, without checking that the diagonal entries are close to one.
With this function, zero-ancilla partial equivalence can be checked as described in the paper "Partial Equivalence Checking of Quantum Circuits" by Chen et al.

Checklist:

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

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (b043e28) 91.3% compared to head (91f06b6) 91.3%.

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #532   +/-   ##
=====================================
  Coverage   91.3%   91.3%           
=====================================
  Files        130     130           
  Lines      13851   13857    +6     
  Branches    2151    2153    +2     
=====================================
+ Hits       12655   12665   +10     
+ Misses      1196    1192    -4     

Flag	Coverage Δ
cpp	91.0% <96.2%> (+<0.1%)	⬆️
python	99.7% <ø> (ø)

Files	Coverage Δ
include/dd/Package.hpp	97.0% <96.2%> (+0.3%)	⬆️

[burgholzer]

Many thanks for the pull request! Overall this is looking really good already. Just a couple of very minor comments that would be nice to address. After that, this is good to go ✅

[burgholzer]

Many thanks for the additional changes. Looking all good now! 😌