change: Move Quasar out to a new package

[kshyatt-aws]

Issue #, if available: N/A

Description of changes: Move Quasar parsing code for OQ3 into its own package to keep this package focused on the simulation portion

Testing done: Unit tests passed locally

Merge Checklist

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General

• I have read the CONTRIBUTING doc
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Tests

• I have added tests that prove my fix is effective or that my feature works (if appropriate)
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[codecov]

Codecov Report

Attention: Patch coverage is 97.77778% with 1 line in your changes missing coverage. Please review.

Project coverage is 98.26%. Comparing base (c813a10) to head (5941f49).

Files with missing lines	Patch %	Lines
src/custom_gates.jl	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #60      +/-   ##
==========================================
- Coverage   98.91%   98.26%   -0.65%     
==========================================
  Files          23       21       -2     
  Lines        3495     2189    -1306     
==========================================
- Hits         3457     2151    -1306     
  Misses         38       38              

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