Implement DS4 model intake

src/app.rs

@@ -63,7 +63,7 @@ impl PreferenceDraft {
             .ok_or_else(|| format!("Unsupported model: {}", preferences.selected_model))?;
         let generation = preferences.generation()?;
         let runtime = preferences.runtime()?;
-        runtime.engine_settings(model)?;
+        runtime.validate(model)?;
         let execution = &runtime.execution;
         let speculative = &runtime.speculative;
         Ok(Self {
@@ -1030,7 +1030,7 @@ impl App {
                 return;
             }
         };
-        if let Err(error) = runtime.engine_settings(model) {
+        if let Err(error) = runtime.validate(model) {
             self.preference_error = Some(error);
             return;
         }