Refactor project scaffolding around FsTreeNode

[AlexanderRichey]

Clean up project scaffolding a bit.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 99.29078% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 96.41%. Comparing base (ae6e810) to head (ae1fba7).
⚠️ Report is 5 commits behind head on refactor.

Files with missing lines	Patch %	Lines
src/core/project/fsUtils.ts	90.90%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##           refactor    #1943      +/-   ##
============================================
+ Coverage     96.28%   96.41%   +0.13%     
============================================
  Files           245      270      +25     
  Lines         12105    13330    +1225     
============================================
+ Hits          11655    12852    +1197     
- Misses          450      478      +28     

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[tejaskash]

Approving, great refactor and I like the AsyncGenerator pattern more than cb's

[aidandaly24]

Makes sense to me I really like how clean the fsTree class and functions are