Add WebAssembly-specific scheduler and update browserwasm condition

[ChrisPulman]

What kind of change does this PR introduce?

update

What is the current behavior?

browserwasm uses TaskPoolScheduler.Default incorrectly

What is the new behavior?

Use WasmScheduler.Default for WebAssembly targets to handle lack of multithreading.

Update the csproj condition for browserwasm to use EndsWith for better compatibility.

What might this PR break?

N/A

Please check if the PR fulfills these requirements

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Other information:

[codecov]

Codecov Report

❌ Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 5.43%. Comparing base (f22ab3c) to head (198bd61).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...veUI.Uno/Builder/UnoReactiveUIBuilderExtensions.cs	0.00%	5 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##            main    #268      +/-   ##
========================================
- Coverage   5.47%   5.43%   -0.04%     
========================================
  Files         16      16              
  Lines        712     717       +5     
  Branches     105     105              
========================================
  Hits          39      39              
- Misses       669     674       +5     
  Partials       4       4              

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.