Update UnbrandedGeneratorVersion to 1.0.0-alpha.20260212.3

[azure-sdk]

This PR updates the UnbrandedGeneratorVersion property in eng/Packages.Data.props and the @typespec/http-client-csharp dependency in eng/packages/http-client-csharp/package.json to version 1.0.0-alpha.20260212.3.

Details

• TypeSpec commit that triggered this PR: microsoft/typespec@5362694

Changes

• Updated eng/Packages.Data.props UnbrandedGeneratorVersion property
• Updated eng/packages/http-client-csharp/package.json dependency version
• Ran npm install to update package-lock.json
• Ran eng/packages/http-client-csharp/eng/scripts/Generate.ps1 to regenerate test projects
• Generated emitter-package.json artifacts using tsp-client
• Regenerated SDK libraries using the unbranded emitter via dotnet msbuild /t:GenerateCode

This is an automated PR created by the TypeSpec publish pipeline.

[Copilot]

Pull request overview

This PR updates the unbranded TypeSpec generator to version 1.0.0-alpha.20260212.3 across the repository's configuration files and regenerates affected artifacts.

Changes:

• Updated UnbrandedGeneratorVersion property and @typespec/http-client-csharp dependency to 1.0.0-alpha.20260212.3
• Regenerated emitter package configuration and SDK test projects with the new generator version

Reviewed changes

Copilot reviewed 2 out of 922 changed files in this pull request and generated no comments.

File	Description
eng/Packages.Data.props	Updated UnbrandedGeneratorVersion property to new version
eng/http-client-csharp-emitter-package.json	Updated @typespec/http-client-csharp dependency to match new version

Files not reviewed (1)

• eng/http-client-csharp-emitter-package-lock.json: Language not supported