chore: v1 implementation of file/designs stub

[jacobrkerstetter]

Description

As title says
Methods related to opening, saving, and inserting files
Other various fixes to get tests running properly

Issue linked

Related to #2388

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 37.71930% with 71 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.23%. Comparing base (5c3c0a2) to head (ab86424).

Files with missing lines	Patch %	Lines
...ys/geometry/core/_grpc/_services/v1/conversions.py	16.12%	26 Missing ⚠️
src/ansys/geometry/core/modeler.py	54.16%	22 Missing ⚠️
src/ansys/geometry/core/designer/design.py	22.72%	17 Missing ⚠️
...nsys/geometry/core/_grpc/_services/v1/materials.py	0.00%	4 Missing ⚠️
...sys/geometry/core/_grpc/_services/v1/components.py	0.00%	1 Missing ⚠️
src/ansys/geometry/core/misc/options.py	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2443      +/-   ##
==========================================
- Coverage   91.56%   91.23%   -0.34%     
==========================================
  Files         169      169              
  Lines       11859    11919      +60     
==========================================
+ Hits        10859    10874      +15     
- Misses       1000     1045      +45     

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