[MSBUILD SDK] Migrate SDK to C#14 extension syntax

[jviau]

Issue describing the changes in this PR

resolves #issue_for_this_pr

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• I have added all required tests (Unit tests, E2E tests)

Additional information

Migrates Azure.Functions.Sdk to use the new C#14 extensions syntax.

https://devblogs.microsoft.com/dotnet/csharp-exploring-extension-members/

[Copilot]

Pull Request Overview

This PR migrates the Azure.Functions.Sdk MSBuild project to use C# 14's new extension syntax, which allows extension methods to be defined more intuitively within extension blocks rather than as static methods in static classes.

Key changes:

• Refactored extension methods from traditional static syntax to C# 14 extension(Type) blocks
• Consolidated helper methods (e.g., Read methods in LockFileExtensions) that were previously scattered
• Removed unused test utility method (WriteNugetConfig)

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
MSBuildExtensions.cs	Converted static extension methods to C# 14 extension syntax for ProjectCreatorTemplates and ProjectCreator
MSBuildLogExtensions.cs	Converted static extension methods to C# 14 extension syntax for TaskLoggingHelper with private helper methods
TaskItemExtensions.cs	Converted static extension methods to C# 14 extension syntax for ITaskItem
LockFileExtensions.cs	Converted to C# 14 extension syntax and added new static helper methods for reading lock files
ExceptionExtensions.cs	Converted static extension methods to C# 14 extension syntax for Exception
ResolveExtensionPackages.cs	Updated to use new LockFile.Read helper method
TempDirectory.cs	Removed unused WriteNugetConfig method
ResolveExtensionPackagesTests.cs	Removed call to deleted WriteNugetConfig method

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[Copilot]

Pull Request Overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 5 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 5 comments.

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