fix: workflow 2b nurbs fixes

[jacobrkerstetter]

Description

changes approximate_curve to interpolate_curve
added copy constructor ability to NURBSCurve class
added length property

Issue linked

Checklist

• I have tested my changes locally.
• I have added necessary documentation or updated existing documentation.
• I have followed the coding style guidelines of this project.
• I have added appropriate unit tests.
• I have reviewed my changes before submitting this pull request.
• I have linked the issue or issues that are solved to the PR if any.
• I have assigned this PR to myself.
• I have added the minimum version decorator to any new backend method implemented.
• I have made sure that the title of my PR follows Conventional commits style (e.g. feat: extrude circle to cylinder)

[codecov]

Codecov Report

❌ Patch coverage is 26.66667% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.77%. Comparing base (80861a5) to head (ef8cc31).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/ansys/geometry/core/shapes/curves/nurbs.py	26.66%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2137      +/-   ##
==========================================
- Coverage   94.87%   94.77%   -0.11%     
==========================================
  Files         141      141              
  Lines       10294    10307      +13     
==========================================
+ Hits         9766     9768       +2     
- Misses        528      539      +11     

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[RobPasMue]

@jacobrkerstetter @jonahrb please add tests for the newly inserted code... We should not merge PRs where the code is not being tested.