Make MidMeasureMP an operator

[albi3ro]

Context:

We've long had issues where MidMeasureMP technically inherits from MeasurementProcess, but it always acts like an Operator. This leads us to problems where methods are missing and our pipeline can't handle it.

Description of the Change:

Makes MidMeasureMP inherit from Operator and makes associated style switches.

Benefits:

Possible Drawbacks:

Related GitHub Issues:

Related Shortcut Stories:
[sc-98587] [sc-51791]

[github-actions]

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Please edit doc/releases/changelog-dev.md with:

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[astralcai]

Now that MidMeasureMP is not a MeasurementProcess anymore, we might want to stop calling it an "MP", potentially we can rename it to just MidMeasure?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.69%. Comparing base (d954267) to head (fab6bf8).
⚠️ Report is 41 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8166      +/-   ##
==========================================
- Coverage   99.69%   99.69%   -0.01%     
==========================================
  Files         548      548              
  Lines       56784    56830      +46     
==========================================
+ Hits        56610    56654      +44     
- Misses        174      176       +2     

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[lillian542]

As discussed in stand I took a look just at the changes to the FTQC module. No concerns on my end!

[PietropaoloFrisoni]

This PR will have consequences (hopefully improvements) for the visualization work with the unified compiler 🤞

[andrijapau]

Looks good to me 😄