Add merge rotation pass

[rmoyard]

Description of the Change:

Add the merge rotations pass, rotations angles are summed in rotation gates removed. It works for multirzop, and customop ({"RX", "RY", "RZ", "PhaseShift", "Rot", "CRX", "CRY", "CRZ", "ControlledPhaseShift", "CRot"}) .

[paul0403]

Note that I added an analysis object in #1186 to check for if a gate operation and its parent gate operation are correctly matched for the purposes of peephole optimizations like merge rotations and cancel inverses. It might be beneficial to merge that PR and use the added analysis if you want.

[paul0403]

Thanks, looks good! Just some small points from me

[codecov]

Codecov Report

Attention: Patch coverage is 93.33333% with 1 line in your changes missing coverage. Please review.

Project coverage is 97.90%. Comparing base (6126963) to head (0213ae7).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
frontend/catalyst/passes.py	93.33%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1162      +/-   ##
==========================================
- Coverage   97.93%   97.90%   -0.03%     
==========================================
  Files          77       77              
  Lines       10921    10935      +14     
  Branches      971      973       +2     
==========================================
+ Hits        10695    10706      +11     
- Misses        179      180       +1     
- Partials       47       49       +2     

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[paul0403]

I think codecov does not cover lit tests. One pytest in https://github.com/PennyLaneAI/catalyst/blob/main/frontend/test/pytest/test_peephole_optimizations.py
(like cancel_inverse) is fine by me, as long as the most expansive tests are at the mlir lit test layer.

[paul0403]

🥳

[rmoyard]

[sc-72014]