Fix WASI build issue

[Kyle-Ye]

Fix WASI pointer overflow. (The only 32 bit platform we support)

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 19.92%. Comparing base (cc6524d) to head (a779e39).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...OpenSwiftUICore/Util/UnsafePointer+Extension.swift	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #142      +/-   ##
==========================================
+ Coverage   19.86%   19.92%   +0.05%     
==========================================
  Files         223      223              
  Lines        6744     6744              
==========================================
+ Hits         1340     1344       +4     
+ Misses       5404     5400       -4     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[Kyle-Ye]

2 remaining issues:

• BitwiseCopyable need Swift 6+ compiler
• PropertyListEncoder is not available on WASI (Seems to be an upstream issue)