Add MidMeasureMP in LightningQubit (cpp only)

[tomlqc]

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---

Context:
Native-execution of circuits with mid-measurements is enabled via the dynamic-one-shot transform. To support the transform, a device must implement methods to apply MidMeasureMP.

MidMeasureMP is a special kind of operation where a sample is drawn from the state vector probability distribution and a projector is applied to the state vector accordingly. It may also support options like reset and post-selection.

The most straightforward way to deal with the requirements is to enhance the state vector class StateVectorLQubit.

This PR is only about the C++ part.

Description of the Change:

Benefits:

Possible Drawbacks:

Related GitHub Issues:

Related GitHub Pull Request:
#621 - See discussions

Related Shortcut Story:
[sc-57704]

[AmintorDusko]

Can we have some tests for unit tests for normalize?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.71%. Comparing base (a3071d3) to head (4022910).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #645      +/-   ##
==========================================
+ Coverage   92.98%   98.71%   +5.72%     
==========================================
  Files          14      173     +159     
  Lines        2368    24506   +22138     
==========================================
+ Hits         2202    24192   +21990     
- Misses        166      314     +148     

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[tomlqc]

Can we have some tests for unit tests for normalize?

Currently it's tested as part of collapse(). But, yes, of course we can have separated tests. I just would have preferred getting the feedback on the previous review.

Actually I may add the separate tests when I commit the Kokkos version, would this be ok?

[AmintorDusko]

Can we have some tests for unit tests for normalize?

Currently it's tested as part of collapse(). But, yes, of course we can have separated tests. I just would have preferred getting the feedback on the previous review.

Actually I may add the separate tests when I commit the Kokkos version, would this be ok?

@tomlqc, we didn't see it before. It is healthy for our software stack to have unit tests, that's how we get the small problems before they turn into big problems.
I will approve for now, and you can proceed with the tests in the next PR.

[tomlqc]

Thanks @AmintorDusko I understand your point. I'll make sure to add the unittest in the next PR.

[vincentmr]

Looks good to me, thanks @tomlqc .