Add MLDSA-44 cosigner implementation

[AlCutter]

This PR adds an implementation of the ML-DSA-44 cosigner recently added to the tlog-cosignature spec.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 73.10345% with 39 lines in your changes missing coverage. Please review.
✅ Project coverage is 75.51%. Comparing base (fa00c16) to head (939d58d).
⚠️ Report is 159 commits behind head on main.

Files with missing lines	Patch %	Lines
note/note_cosigv1.go	72.91%	23 Missing and 16 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #247      +/-   ##
==========================================
- Coverage   82.57%   75.51%   -7.07%     
==========================================
  Files           5        8       +3     
  Lines         241      686     +445     
==========================================
+ Hits          199      518     +319     
- Misses         30       96      +66     
- Partials       12       72      +60     

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