Improve exception handling in IsNuGetPluginValid to prevent unnecessary restores

[Copilot]

The IsNuGetPluginValid method was catching all exceptions from FileVersionInfo.GetVersionInfo and assuming the plugin was invalid, which could trigger unnecessary dotnet restore operations on systems where version checking consistently fails due to file format issues.

Problem

On some systems, FileVersionInfo.GetVersionInfo throws NotSupportedException when the file format isn't supported for version reading, even though the plugin DLL itself is perfectly valid. The previous implementation treated all exceptions the same way:

catch (Exception ex)
{
    logger?.LogDebug(ex, "Error checking version for NuGet plugin: {dllPath}", plugin.DllPath);
    return false; // Assume invalid if we can't check version
}

This caused unnecessary dotnet restore operations to run repeatedly on systems with consistent file format issues.

Solution

Now differentiates between exception types with more appropriate fallback behavior:

• NotSupportedException: Logs a warning and assumes the plugin is valid (returns true)
• Other exceptions: Logs an error and assumes the plugin is invalid (returns false)

catch (NotSupportedException ex)
{
    logger?.LogWarning(ex, "File format not supported when checking version for NuGet plugin: {dllPath}. Assuming valid.", plugin.DllPath);
    return true; // Assume valid if file format is not supported
}
catch (Exception ex)
{
    logger?.LogError(ex, "Unexpected error checking version for NuGet plugin: {dllPath}. Assuming invalid.", plugin.DllPath);
    return false; // Assume invalid for other exceptions
}

Testing

Added comprehensive tests to verify both exception handling paths:

• IsNuGetPluginValid_WithNotSupportedException_ReturnsTrue
• IsNuGetPluginValid_WithOtherException_ReturnsFalseAndLogsError

All existing tests continue to pass (103 total: 98 succeeded, 5 skipped, 0 failed).

Fixes #53.

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[matt-goldman]

LGTM

[Copilot]

Pull Request Overview

This PR improves exception handling in the IsNuGetPluginValid method to prevent unnecessary dotnet restore operations caused by file format exceptions. The change differentiates between NotSupportedException (assumes plugin is valid) and other exceptions (assumes plugin is invalid), reducing redundant restore operations on systems with consistent file format issues.

• Adds specific handling for NotSupportedException to assume plugin validity
• Changes generic exception handling to log errors instead of debug messages
• Adds comprehensive test coverage for both exception handling paths

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/Blake.BuildTools/Utils/PluginLoader.cs	Updates exception handling logic to differentiate between NotSupportedException and other exceptions
tests/Blake.BuildTools.Tests/Utils/PluginLoaderTests.cs	Adds two new test methods and enhances TestLogger to capture warning messages