fs: remove permissions fallback

[avivkeller]

Now that the permissions system is multi-threaded (#65392), we can remove the single-threaded fallback for directory recursion

[codecov]

Codecov Report

❌ Patch coverage is 92.10526% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.01%. Comparing base (46bbfc4) to head (33fca90).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/node_file.cc	91.89%	0 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #65990      +/-   ##
==========================================
+ Coverage   89.98%   90.01%   +0.03%     
==========================================
  Files         784      784              
  Lines      268361   268265      -96     
  Branches    51117    51115       -2     
==========================================
- Hits       241478   241473       -5     
+ Misses      17438    17339      -99     
- Partials     9445     9453       +8     

Files with missing lines	Coverage Δ
lib/fs.js	98.36% <100.00%> (+1.04%)	⬆️
lib/internal/fs/promises.js	91.66% <ø> (+0.84%)	⬆️
lib/internal/fs/utils.js	98.25% <ø> (+1.96%)	⬆️
src/node_file.cc	75.66% <91.89%> (+0.12%)	⬆️

... and 22 files with indirect coverage changes

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