feat: update hugr-passes to use visibility

[acl-cqc]

Pulled out from #2143, which this follows.

[codecov]

Codecov Report

❌ Patch coverage is 85.07463% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 82.00%. Comparing base (5bbe0cd) to head (c510053).
⚠️ Report is 334 commits behind head on main.

Files with missing lines	Patch %	Lines
hugr-passes/src/dead_funcs.rs	85.00%	3 Missing ⚠️
hugr-passes/src/monomorphize.rs	75.00%	1 Missing and 2 partials ⚠️
hugr-passes/src/const_fold.rs	87.50%	2 Missing ⚠️
hugr-passes/src/dead_code.rs	83.33%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2418      +/-   ##
==========================================
- Coverage   82.01%   82.00%   -0.02%     
==========================================
  Files         245      246       +1     
  Lines       45474    45524      +50     
  Branches    41210    41260      +50     
==========================================
+ Hits        37297    37331      +34     
- Misses       6172     6187      +15     
- Partials     2005     2006       +1     

Flag	Coverage Δ
python	85.38% <ø> (ø)
rust	81.65% <85.07%> (-0.02%)	⬇️

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[acl-cqc]

I think this can be said to have be been superceded by #2836 and #2871