refactor(display): improve touch handling and code formatting

libraries/KlubhausCore/src/DoorbellLogic.cpp

@@ -258,3 +258,13 @@ void DoorbellLogic::onSerialCommand(const String& cmd) {
     }
     else Serial.println(F("[CMD] alert|silence|reboot|dashboard|off|status"));
 }
+
+void DoorbellLogic::setScreen(ScreenID s) {
+    Serial.printf("[SCREEN] Set to %s\n", screenIdStr(s));
+    _state.screen = s;
+    
+    // Auto-manage backlight based on screen
+    bool needsBacklight = (s != ScreenID::OFF);
+    _display->setBacklight(needsBacklight);
+    _state.backlightOn = needsBacklight;
+}

libraries/KlubhausCore/src/DoorbellLogic.h

@@ -34,6 +34,7 @@ private:
     void flushStatus(const String& message);
     void heartbeat();
     void transition(DeviceState s);
+    void setScreen(ScreenID s);
     String topicUrl(const char* base);
 
     DisplayManager* _display;