Unify the shutdown proceedure (#7393)

* Unify the shutdown proceedure

* Don't double save nodeDB on shutdown

* Re-tool button shutdown to better correspond to tones

* Beep then save

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Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/modules/SystemCommandsModule.cpp

@@ -107,11 +107,7 @@ int SystemCommandsModule::handleInputEvent(const InputEvent *event)
         return true;
     // Power control
     case INPUT_BROKER_SHUTDOWN:
-        LOG_ERROR("Shutting Down");
-        IF_SCREEN(screen->showSimpleBanner("Shutting Down..."));
-        nodeDB->saveToDisk();
-        shutdownAtMsec = millis() + DEFAULT_SHUTDOWN_SECONDS * 1000;
-        // runState = CANNED_MESSAGE_RUN_STATE_INACTIVE;
+        shutdownAtMsec = millis();
         return true;
 
     default: