Few shape/free func related fixes

[adam-urbanczyk]

• Fix uIsoMatrix and vIsoMatrix single float param handling
• Use a more robust solver for constrainedApproximate2D
• Rework check to produce output (warnings) by default
• Add Shape.reverse
• Extend siblings to support multiple levels at once
• Fix solid free function handling of multiple inner cavities
• Add offset2D
• Tests

[codecov]

Codecov Report

❌ Patch coverage is 98.91304% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 95.64%. Comparing base (a637795) to head (b1b6af1).

Files with missing lines	Patch %	Lines
cadquery/occ_impl/shapes.py	98.75%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2033      +/-   ##
==========================================
+ Coverage   95.62%   95.64%   +0.02%     
==========================================
  Files          30       30              
  Lines        8893     8962      +69     
  Branches     1311     1328      +17     
==========================================
+ Hits         8504     8572      +68     
  Misses        240      240              
- Partials      149      150       +1     

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