Refactor duplicated command-line provider boilerplate into shared base class

[Copilot]

Duplicate-code analysis identified repeated ICommandLineOptionsProvider scaffolding across diagnostic/extension providers, with identical metadata, enablement, option-caching, and default validation structure. This change extracts that shared structure and keeps provider-specific validation logic local.

• What changed

  • Added CommandLineOptionsProviderBase in Microsoft.Testing.Platform to centralize:
    • extension metadata (Uid, Version, DisplayName, Description)
    • IsEnabledAsync() default behavior
    • cached GetCommandLineOptions()
    • default no-op validation methods

• Provider migrations (behavior preserved)

  • Refactored:
    • HangDumpCommandLineProvider
    • CrashDumpCommandLineProvider
    • MSBuildCommandLineProvider
  • Each provider now passes static option definitions + metadata via base constructor and overrides only provider-specific validation.

• Coverage for new abstraction

  • Added focused unit tests for CommandLineOptionsProviderBase defaults and constructor-supplied options surface.

internal sealed class HangDumpCommandLineProvider : CommandLineOptionsProviderBase
{
    public HangDumpCommandLineProvider()
        : base(
            nameof(HangDumpCommandLineProvider),
            ExtensionVersion.DefaultSemVer,
            ExtensionResources.HangDumpExtensionDisplayName,
            ExtensionResources.HangDumpExtensionDescription,
            CachedCommandLineOptions)
    {
    }

    public override Task<ValidationResult> ValidateOptionArgumentsAsync(CommandLineOption commandOption, string[] arguments)
    {
        // HangDump-specific checks only
    }
}

[Copilot]

Pull request overview

This PR refactors repeated ICommandLineOptionsProvider boilerplate across multiple Platform extensions into a shared CommandLineOptionsProviderBase abstraction within Microsoft.Testing.Platform, and adds unit tests to validate the new base defaults.

Changes:

• Introduce CommandLineOptionsProviderBase to centralize provider metadata, enablement default, option caching, and default validation behavior.
• Migrate HangDump, CrashDump, and MSBuild command-line providers to inherit from the new base class.
• Add unit tests covering default base behavior and constructor-supplied options exposure.

Show a summary per file

File	Description
test/UnitTests/Microsoft.Testing.Platform.UnitTests/CommandLine/CommandLineOptionsProviderBaseTests.cs	Adds unit tests validating the new base class defaults and option passthrough.
src/Platform/Microsoft.Testing.Platform/CommandLine/CommandLineOptionsProviderBase.cs	Introduces the shared base class for command-line option providers.
src/Platform/Microsoft.Testing.Extensions.MSBuild/MSBuildCommandLineProvider.cs	Refactors MSBuild provider to use the shared base + cached options.
src/Platform/Microsoft.Testing.Extensions.HangDump/HangDumpCommandLineProvider.cs	Refactors HangDump provider to use the shared base and override validation.
src/Platform/Microsoft.Testing.Extensions.CrashDump/CrashDumpCommandLineProvider.cs	Refactors CrashDump provider to use the shared base and override validation.

Copilot's findings

• Files reviewed: 5/5 changed files
• Comments generated: 1

[Copilot]

Copilot's findings

• Files reviewed: 18/18 changed files
• Comments generated: 2