V14: Fix up install controller (#15646)

* Rename InstallVResponseModel to InstallRequestModel

* Align SettingsInstallController

* Rename split DatabaseInstallResponseModel in two

* Change UserInstallResponseModel to UserInstallViewModel

* Use PresentationModel instead of ViewModel

* Use operation status pattern when validating database

* Prepare for install to return a message

* Begin updating steps

* Make StepBase sharable between upgrade and install

* Update steps

* Use error message from install steps in install controller

* Use error message from upgrade steps in upgrade controller

* Use 500 for install/upgrade failed

It's entirely likely that it has nothing to do with the request

* Updated OpenApi.Json

---------

Co-authored-by: Bjarke Berg <mail@bergmania.dk>

src/Umbraco.Core/Installer/StepBase.cs

@@ -0,0 +1,12 @@
+using Umbraco.Cms.Core.Models.Installer;
+
+namespace Umbraco.Cms.Core.Installer;
+
+public abstract class StepBase
+{
+    protected Attempt<InstallationResult> FailWithMessage(string message)
+        => Attempt<InstallationResult>.Fail(new InstallationResult { ErrorMessage = message });
+
+
+    protected Attempt<InstallationResult> Success() => Attempt<InstallationResult>.Succeed(new InstallationResult());
+}