Add ProposedViewSize and LayoutTraits API

[Kyle-Ye]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 41.37931% with 51 lines in your changes missing coverage. Please review.

Project coverage is 21.91%. Comparing base (c1be12f) to head (fb8cf99).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...OpenSwiftUICore/Layout/Geometry/LayoutTraits.swift	50.00%	36 Missing ⚠️
...OpenSwiftUICore/Layout/View/ProposedViewSize.swift	0.00%	15 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #195      +/-   ##
==========================================
+ Coverage   21.76%   21.91%   +0.14%     
==========================================
  Files         301      303       +2     
  Lines       12069    12156      +87     
==========================================
+ Hits         2627     2664      +37     
- Misses       9442     9492      +50     

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