Add breaking change documentation for NuGet packages excluded from deps.json files

[Copilot]

This PR adds comprehensive documentation for a breaking change introduced in .NET 10 Preview 5 where NuGet packages that don't contribute runtime assets may be excluded from deps.json files.

Changes Made

New Breaking Change Document: Created docs/core/compatibility/deployment/10.0/deps-json-trimmed-packages.md that documents:

• Previous behavior: All referenced NuGet packages and projects were included in deps.json as library entries, even without runtime assets
• New behavior: Libraries may be excluded if they don't contribute runtime assets and their removal doesn't break dependency paths
• Workaround: Set the TrimDepsJsonLibrariesWithoutAssets MSBuild property to false to disable the new behavior

Documentation Updates:

• Added new "Deployment" section to the .NET 10 compatibility index (docs/core/compatibility/10.0.md)
• Updated the table of contents (docs/core/compatibility/toc.yml) to include the new document

The documentation follows established Microsoft Writing Style Guidelines and includes proper AI usage disclosure. This change improves accuracy of dependency tracking and reduces false positives in security scanners that process deps.json files.

Example workaround:

<PropertyGroup>
  <TrimDepsJsonLibrariesWithoutAssets>false</TrimDepsJsonLibrariesWithoutAssets>
</PropertyGroup>

Fixes #48132.

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Internal previews

📄 File	🔗 Preview link
docs/core/compatibility/10.0.md	Breaking changes in .NET 10
docs/core/compatibility/sdk/10.0/deps-json-trimmed-packages.md	NuGet packages with no runtime assets aren't included in deps.json
docs/core/compatibility/toc.yml	docs/core/compatibility/toc