Symbol package publishing

[carldebilly]

This PR configures the project for symbol package publishing to NuGet by adding support for .snupkg symbol packages and optimizing the CI build configuration.

• Enables symbol package creation and publishing with proper source embedding
• Updates CI pipeline to run on Ubuntu and handle both .nupkg and .snupkg files
• Optimizes build configuration by disabling unnecessary cloud build features

[Copilot]

Pull Request Overview

This PR configures the project for symbol package publishing to NuGet by adding support for .snupkg symbol packages and optimizing the CI build configuration.

• Enables symbol package creation and publishing with proper source embedding
• Updates CI pipeline to run on Ubuntu and handle both .nupkg and .snupkg files
• Optimizes build configuration by disabling unnecessary cloud build features

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
version.json	Disables cloud build variables and build numbering for optimized CI
Directory.Build.props	Adds source embedding and CI build detection for symbol packages
.github/workflows/build.yml	Updates runner OS and adds symbol package handling to build and publish steps

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