[WIP] Evaluate the usage of Microsoft.Extensions.FileSystemGlobbing as the backing implementation for IMSBuildGlob

[Copilot]

• [ ] Add Microsoft.Extensions.FileSystemGlobbing package reference to Microsoft.Build project
• [ ] Create FileSystemGlobbingMSBuildGlob class implementing IMSBuildGlob using Microsoft.Extensions.FileSystemGlobbing
• [ ] Add trait/feature flag to choose between original MSBuildGlob and new FileSystemGlobbingMSBuildGlob implementations
• [ ] Update MSBuildGlob.Parse() method to optionally return the new implementation based on feature flag
• [ ] Create test infrastructure to test both implementations with the same test cases
• [ ] Update existing MSBuildGlob tests to run against both implementations
• [ ] Ensure behavioral compatibility between the two implementations
• [ ] Validate that all existing tests pass with both implementations

Fixes #12032.

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