feat(logs): add NLog integration

[Flash0ver]

closes #5167

Changes

Add NLog integration to Sentry Structured Logging.

Docs

• TODO

[codecov]

Codecov Report

❌ Patch coverage is 94.91525% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 74.14%. Comparing base (a2318ff) to head (de54732).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/Sentry.NLog/LogLevelExtensions.cs	72.72%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5176      +/-   ##
==========================================
+ Coverage   74.07%   74.14%   +0.06%     
==========================================
  Files         501      503       +2     
  Lines       18113    18172      +59     
  Branches     3521     3530       +9     
==========================================
+ Hits        13417    13473      +56     
- Misses       3837     3839       +2     
- Partials      859      860       +1     

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