Add telemetry tracking for task factory names and runtime usage

[Copilot]

Context

MSBuild needs visibility into TaskFactory usage patterns to inform deprecation decisions. This PR implements telemetry to track which task factories are being used for task execution, including custom factories and the deprecated CodeTaskFactory.

Changes Made

TaskExecutionStats.cs

• Added TaskFactoryName property to track which factory created each task (AssemblyTaskFactory, CodeTaskFactory, RoslynCodeTaskFactory, XamlTaskFactory, IntrinsicTaskFactory, or custom factory names)
• Added TaskHostRuntime property to track out-of-process execution runtime ("CLR2", "CLR4", "NET", or null)
• Updated Accumulate, Equals, and GetHashCode methods to include new properties

TelemetryDataUtils.cs

• Enhanced to hash custom (non-MSBuild) task factory names for privacy
• Known factories (AssemblyTaskFactory, CodeTaskFactory, RoslynCodeTaskFactory, XamlTaskFactory, IntrinsicTaskFactory, TaskHostFactory) are not hashed
• Hashing protects proprietary/internal factory names while still providing usage data

WorkerNodeTelemetryData.cs, WorkerNodeTelemetryEventArgs.cs

• Updated to propagate factory name and runtime information through telemetry pipeline
• Factory data is now included in task execution details sent to telemetry consumers
• Fixed parameter name typo: cumulativeExectionTime → cumulativeExecutionTime
• Updated to use consistent collection expressions ([])

ProjectTelemetry.cs

• Refactored for cleaner code structure with AddCountIfNonZero helper method (renamed from AddIfNotEmpty for clarity)
• Maintains existing telemetry events (build/tasks/taskfactory, build/tasks, build/tasks/msbuild-subclassed)

Telemetry_Tests.cs

• Added WorkerNodeTelemetryCollection_TaskFactoryName test to verify factory names are captured for both built-in and inline tasks
• Added TelemetryDataUtils_HashesCustomFactoryName test to verify custom factory names are hashed while known factories are not
• Enhanced existing tests to verify factory names and runtime information are populated

ProjectTelemetry_Tests.cs

• Maintained existing tests for MSBuild task subclassing tracking

Testing

• All ProjectTelemetry unit tests pass (6/6)
• All Telemetry integration tests pass (19/19, including 2 new comprehensive tests)
• Build succeeds with zero warnings
• Verified factory names are captured for built-in tasks (AssemblyTaskFactory)
• Verified factory names are captured for inline tasks (RoslynCodeTaskFactory)
• Verified IntrinsicTaskFactory is correctly recognized as a known factory
• Verified custom factory names are properly hashed for privacy
• Verified task host runtime information is correctly tracked

Notes

This telemetry captures factory information for ALL tasks (not just custom ones) and associates it with individual task execution statistics. This approach provides comprehensive visibility into:

• CodeTaskFactory usage to inform deprecation decisions (Deprecate and restrict non-MSBuild TaskFactory implementations #12347)
• Custom task factory adoption and usage patterns
• Task host runtime preferences across the ecosystem
• Data to support TaskFactory support and deprecation decisions

Original prompt

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This section details on the original issue you should resolve

<issue_title>Collect telemetry to see the features usage</issue_title>
<issue_description>Use existing telemetry infrastructure, collect telemetry to see the usage for:

1. Non-MSBuild TaskFactory implementations (so we can proceed with Deprecate and restrict non-MSBuild TaskFactory implementations #12347)
2. CodeTaskFactory</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Collect telemetry to see the features usage #12988

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[dotnet-policy-service]

Hello @@copilot, I noticed that you’re changing an .swr file or any file under src/Package/MSBuild.VSSetup.. Please make sure to validate this change by an experimental VS insertion. This is accomplished by pushing to an exp/* branch, which requires write permissions to this repo.

[YuliiaKovalova]

@copilot update description according to the pushed changes

[Copilot]

@copilot update description according to the pushed changes

Updated the PR description to reflect the refactored implementation that tracks factory name and runtime in TaskExecutionStats rather than using a separate dictionary in ProjectTelemetry. The new approach captures this information for all tasks and includes it in the worker node telemetry data.

[Copilot]

Pull request overview

This pull request adds telemetry tracking for task factory usage patterns to inform deprecation decisions for custom TaskFactory implementations and CodeTaskFactory. The implementation extends the existing telemetry infrastructure to capture and report task factory names alongside task execution statistics.

Key Changes

• Extended TaskExecutionStats to include TaskFactoryName and TaskHostRuntime fields
• Updated telemetry serialization to transmit factory information across worker nodes
• Added hashing logic for custom factory names while keeping built-in factory names readable
• Modified telemetry collection points to capture and forward factory information

Reviewed changes

Copilot reviewed 13 out of 14 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/Framework/Telemetry/TaskExecutionStats.cs	Added TaskFactoryName and TaskHostRuntime properties to track factory metadata
src/Framework/Telemetry/WorkerNodeTelemetryData.cs	Updated AddTask method signature to accept factory parameters; modernized constructor with collection expressions
src/Framework/Telemetry/WorkerNodeTelemetryEventArgs.cs	Extended serialization to include factory name and runtime fields
src/Framework/Telemetry/TelemetryDataUtils.cs	Added KnownTaskFactoryNames list and hashing logic for custom factory names
src/Build/TelemetryInfra/ITelemetryForwarder.cs	Extended AddTask interface with factory parameters
src/Build/TelemetryInfra/TelemetryForwarderProvider.cs	Updated implementations to pass factory information through telemetry pipeline
src/Build/BackEnd/Components/RequestBuilder/RequestBuilder.cs	Modified task statistics collection to extract and forward factory metadata
src/Build/BackEnd/Components/Logging/ProjectTelemetry.cs	Refactored property building with AddIfNotEmpty helper; improved TryGetValue pattern usage
src/Build.UnitTests/Telemetry/Telemetry_Tests.cs	Added tests for factory name tracking and hashing behavior
src/Framework.UnitTests/WorkerNodeTelemetryEventArgs_Tests.cs	Updated serialization test with factory parameters
src/Build.UnitTests/BackEnd/ProjectTelemetry_Tests.cs	Formatting cleanup
src/Tasks.UnitTests/TelemetryTaskTests.cs	Removed empty comment lines
src/Framework/TelemetryEventArgs.cs	Minor formatting (blank line)
src/Build/TelemetryInfra/InternalTelemetryConsumingLogger.cs	Minor formatting (blank lines)