When running MTP applications with invalid command-line arguments, error messages previously only showed the problematic option without context about the complete command that was executed. This made debugging difficult in automation scenarios where users might not see the actual command being invoked.

Problem

The original error message was not helpful for debugging:

Option '--dotnet-test-pipe' from provider 'Platform command line provider' (UID: PlatformCommandLineProvider) expects at most 1 arguments

In automation scenarios like CI/CD pipelines, users often don't see the exact command being run, making it hard to understand what went wrong.

Solution

Added a new ToCommandLine() method to CommandLineParseResult that reconstructs the full command from parsed options. Updated validation error messages to include the complete command that was executed.

After

The error message now includes the full command for better debugging:

Option '--dotnet-test-pipe' from provider 'Platform command line provider' (UID: PlatformCommandLineProvider) expects at most 1 arguments. Command: /path/to/TestProject.dll --dotnet-test-pipe arg1 arg2

Changes Made

• Added ToCommandLine() method: Reconstructs the command line from CommandLineParseResult including tool name, options, and arguments
• Updated error message resources: Modified PlatformResources.resx to include command context in validation error messages
• Updated validation logic: Modified CommandLineOptionsValidator to use the reconstructed command in error messages
• Updated localization files: Updated all .xlf files with new source strings for proper localization support
• Updated tests: Modified ArgumentArityTests to reflect new error message format

Implementation Details

The ToCommandLine() method properly handles:

• Tool names and executable paths
• Multiple options with arguments
• Arguments containing spaces (properly quoted)
• Edge cases like empty options or missing tool names

This is a minimal change that only affects error message formatting without modifying parsing logic or public APIs.

Fixes #6194.

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