on settings save, return the new settings.

update the frontend to persist settings to the database.
Using ScrutinyConfigService instead of TreoConfigService.
Using snake case settings in frontend.
Make sure we're using AppConfig type where possible.

webapp/frontend/src/app/modules/detail/detail.component.html

@@ -4,7 +4,7 @@
 
         <div class="flex items-center justify-between w-full my-4 px-4 xs:pr-0">
             <div class="mr-6">
-                <h2 class="m-0">Drive Details - {{device | deviceTitle:config.dashboardDisplay}} </h2>
+                <h2 class="m-0">Drive Details - {{device | deviceTitle:config.dashboard_display}} </h2>
                 <div class="text-secondary tracking-tight">Dive into S.M.A.R.T data</div>
             </div>
             <!-- Action buttons -->
@@ -126,7 +126,7 @@
                         <div class="text-secondary text-md">Powered On</div>
                     </div>
                     <div class="my-2 col-span-2 lt-md:col-span-1">
-                        <div>{{smart_results[0]?.temp | temperature:config.temperatureUnit:true}}</div>
+                        <div>{{smart_results[0]?.temp | temperature:config.temperature_unit:true}}</div>
                         <div class="text-secondary text-md">Temperature</div>
                     </div>
                 </div>