Add Windows startup plugin

[JSCU-CNI]

This PR adds support for Windows startup folder and registry persistence artifacts.

[codecov]

Codecov Report

❌ Patch coverage is 86.58537% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.04%. Comparing base (a5d10e4) to head (22f615a).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
dissect/target/plugins/os/windows/startup.py	89.55%	7 Missing ⚠️
dissect/target/plugins/os/windows/registry.py	73.33%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1585      +/-   ##
==========================================
+ Coverage   81.02%   81.04%   +0.01%     
==========================================
  Files         400      401       +1     
  Lines       34937    35047     +110     
==========================================
+ Hits        28307    28403      +96     
- Misses       6630     6644      +14     

Flag	Coverage Δ
unittests	81.04% <86.58%> (+0.01%)	⬆️

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[codspeed-hq]

Merging this PR will not alter performance

✅ 12 untouched benchmarks

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_{Comparing JSCU-CNI:windows-startup-plugin (22f615a) with main (54808a5)}