impl(auth): handle etags for boundaries

[alvarowolfx]

Towards #4186

[codecov]

Codecov Report

❌ Patch coverage is 86.58537% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 93.90%. Comparing base (305abcb) to head (1c8c1a9).
⚠️ Report is 18 commits behind head on main.

Files with missing lines	Patch %	Lines
src/auth/src/access_boundary.rs	86.58%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4911      +/-   ##
==========================================
- Coverage   93.93%   93.90%   -0.03%     
==========================================
  Files         221      221              
  Lines        8538     8601      +63     
==========================================
+ Hits         8020     8077      +57     
- Misses        518      524       +6     

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[alvarowolfx]

/gcbrun