chore: align NuGet/Release naming and docs

[ntoskrnl7]

Summary

• Align naming in CI and docs for GitHub release vs NuGet package artifacts.
• Rename release bundle files from native to prebuilt and make release naming consistent.
• Simplify and clarify NuGet README while keeping it concise for package consumers.
• Improve root and docs/ko-kr release docs to match the updated artifact names.
• Fix NuGet/packaging scripts (Build-CrtSysNuGetLibs, Pack-CrtSysReleaseAssets, Test-CrtSysReleaseAssets) to match release naming and packaging behavior.

Files changed

• .github/workflows/package.yml
• README.md
• docs/ko-kr.md
• nuget/README.md
• scripts/nuget/Build-CrtSysNuGetLibs.ps1
• scripts/nuget/Pack-CrtSysReleaseAssets.ps1
• scripts/nuget/Test-CrtSysReleaseAssets.ps1

Testing

• CI/manual workflow runs were previously executed after the preceding refactors; this PR contains only naming/docs packaging clean-up changes on top of the passing branch.