This PR updates all Microsoft.Extensions.AI* package references throughout the repository to their latest stable versions.

Package Updates

The following packages have been updated in Directory.Packages.props:

• Microsoft.Extensions.AI.Abstractions: 9.10.0 → 9.10.1
• Microsoft.Extensions.AI: 9.10.0 → 9.10.1
• Microsoft.Extensions.AI.OpenAI: 9.10.0-preview.1.25513.3 → 9.10.1-preview.1.25521.4

Changes

Only Directory.Packages.props was modified (2 lines):

• Updated the MicrosoftExtensionsAIVersion property from 9.10.0 to 9.10.1
• Updated the explicit Microsoft.Extensions.AI.OpenAI package version to 9.10.1-preview.1.25521.4

All project files (.csproj) use central package management and inherit these versions automatically, so no additional changes were required.

Verification

✅ Build Status: Clean build with 0 warnings and 0 errors
✅ Test Results: All 1,951 tests passed across .NET 8.0, 9.0, and 10.0 target frameworks
✅ Compatibility: No breaking changes or code modifications required
✅ Security: CodeQL analysis shows no new vulnerabilities

The latest package versions were queried directly from NuGet.org to ensure accuracy. All code compiles successfully and maintains full backward compatibility with the updated dependencies.

This pull request was created as a result of the following prompt from Copilot chat.

Update all Microsoft.Extensions.AI* package references to the latest 9.10.1* versions throughout the repo. This includes:

1. In Directory.Packages.props, ensure all PackageVersion lines for Microsoft.Extensions.AI, Microsoft.Extensions.AI.Abstractions, and Microsoft.Extensions.AI.OpenAI use version 9.10.1 (or 9.10.1* if wildcards are supported/preferred).
2. Remove or replace any older preview or patch versions (such as 9.10.0-preview.1.25513.3) with 9.10.1*.
3. For all csproj files (such as samples/ChatWithTools/ChatWithTools.csproj), ensure Microsoft.Extensions.AI* package references do not override the central version or, if specified, use 9.10.1*.
4. Run a build to verify no dependency conflicts and all code referencing Microsoft.Extensions.AI* compiles successfully.

Only update package references—no code changes unless required for compatibility with the new version. If any compatibility issues arise during build/test, document them in the PR and propose minimal fixes.

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