Add lookup table to TaskExecutionHost to eliminate hot-path allocations

[Copilot]

Fixes #11959 (assuming this is the issue number - please update)

Context

EnsureParameterInitialized concatenates strings on every parameter initialization:

string key = "DisableLogTaskParameter_" + _taskName + "_" + parameter.Name;

This allocates on the hot path during task execution.

Changes Made

TaskFactoryWrapper.cs

• Added DisableLogTaskParameterKeys and DisableLogTaskParameterItemMetadataKeys dictionaries to PropertyData
• Precompute lookup keys in PopulatePropertyInfo() during task factory initialization
• Exposed GetDisableLogTaskParameterKey() and GetDisableLogTaskParameterItemMetadataKey() to retrieve precomputed strings

TaskExecutionHost.cs

• Replaced string concatenation with dictionary lookups:

// Before: allocates on every call
string key = "DisableLogTaskParameter_" + _taskName + "_" + parameter.Name;

// After: retrieves precomputed string
string key = _taskFactoryWrapper.GetDisableLogTaskParameterKey(parameter.Name);

Testing

• All TaskExecutionHost and TaskFactory unit tests pass
• Verified with sample and real-world project builds

Notes

Keys are computed once per task factory and reused across all parameter initializations, eliminating allocations from the hot path.

Original prompt

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This section details on the original issue you should resolve

<issue_title>add a lookup table to TaskExecutionHost.cs</issue_title>
<issue_description>During a review discussion for PR that optimizes TaskExecutionHost
We've come to conclusion that it is a step in a good direction, however there is a further improvement to be had: #11959 (comment)

We can skip string key = "DisableLogTaskParameter_" + _taskName + "_" + parameter.Name; which allocates by instead building a lookup table when we have the available set of tasks and parameter names and then fetching the strings from there.

Task:
build said lookup table to lower the allocations on the hot path further.</issue_description>

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

• Fixes add a lookup table to TaskExecutionHost.cs #12056

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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.