Fix code review issues: Remove dynamic keyword and improve error handling

1. DotNetResources.cs: Replace dynamic keyword with reflection-based property access. Use indexed access instead of Last() to avoid potential exceptions.

2. DotNetCommandExecutor.cs: Improve error handling to throw exceptions on any non-zero exit code, not just when stderr has content. Provides clear error messages for both cases.

Co-authored-by: jongalloway <[email protected]>

Author: Copilot

DotNetMcp/DotNetCommandExecutor.cs

@@ -132,10 +132,13 @@ public static async Task<string> ExecuteCommandForResourceAsync(string arguments
         var error = await process.StandardError.ReadToEndAsync();
         await process.WaitForExitAsync();
 
-        if (process.ExitCode != 0 && !string.IsNullOrEmpty(error))
+        if (process.ExitCode != 0)
         {
             logger?.LogError("Command failed with exit code {ExitCode}: {Error}", process.ExitCode, error);
-            throw new InvalidOperationException($"dotnet command failed: {error}");
+            var errorMessage = !string.IsNullOrEmpty(error)
+                ? $"dotnet command failed: {error}"
+                : $"dotnet command failed with exit code {process.ExitCode} and no error output.";
+            throw new InvalidOperationException(errorMessage);
         }
 
         logger?.LogDebug("Command completed successfully");

DotNetMcp/DotNetResources.cs

@@ -46,10 +46,11 @@ public async Task<string> GetSdkInfo()
                 }
             }
 
+            var lastSdk = sdks.Count > 0 ? sdks[sdks.Count - 1] : null;
             var response = new
             {
                 sdks,
-                latestSdk = sdks.LastOrDefault() != null ? ((dynamic)sdks.Last()).version : null
+                latestSdk = lastSdk?.GetType().GetProperty("version")?.GetValue(lastSdk) as string
             };
 
             return JsonSerializer.Serialize(response, new JsonSerializerOptions { WriteIndented = true });