Apply suggestions from code review

Thanks Patrick!

Co-authored-by: Patrick Meinecke <SeeminglyScience@users.noreply.github.com>

Author: andyleejordan

src/PowerShellEditorServices/Services/PowerShell/Host/PsesInternalHost.cs

@@ -329,7 +329,7 @@ public async Task<bool> TryStartAsync(HostStartOptions startOptions, Cancellatio
                     function global:PSConsoleHostReadLine { $global:__psEditorServices_userInput }
 
                     # Execute the provided shell integration script.
-                    try { . "{{startOptions.ShellIntegrationScript}}" } catch {}
+                    try { . '{{startOptions.ShellIntegrationScript}}' } catch {}
                     """;
                 await EnableShellIntegrationAsync(setupShellIntegration, cancellationToken).ConfigureAwait(false);
                 _logger.LogDebug("Shell integration enabled!");
@@ -1085,7 +1085,7 @@ private void InvokeInput(string input, CancellationToken cancellationToken)
                 {
                     // Save the user's input to our special global variable so PSConsoleHostReadLine can read it.
                     InvokePSCommand(
-                        new PSCommand().AddScript($"$global:__psEditorServices_userInput = \"{input}\""),
+                        new PSCommand().AddScript("$global:__psEditorServices_userInput = $args[0]").AddArgument(input),
                         new PowerShellExecutionOptions { ThrowOnError = false, WriteOutputToHost = false },
                         cancellationToken);