New kernel drivers and device implementation updates (#561)

- Added modular device support and devicetree bindings for ILI9341, ILI9488, CST816S, XPT2046, and GPIO button input, updating several board configurations for display/touch/backlight/keyboard/battery.
- Added a setting to control deprecated HAL usage (device property + Kconfig).

TactilityKernel/private/tactility/device_listener_internal.h

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/device_listener.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Internal to TactilityKernel: invoked by device lifecycle code (device_start/device_stop) to
+// notify all registered listeners of a device state transition. Not part of the public API -
+// external code only sees device_listener_add()/device_listener_remove().
+void device_listener_notify(struct Device* dev, enum DeviceEvent event);
+
+#ifdef __cplusplus
+}
+#endif