Finished Timer IRQ abstraction

Core/Src/Reg/SHAL_TIM_CALLBACK.cpp

@@ -0,0 +1,9 @@
+//
+// Created by Luca on 8/28/2025.
+//
+
+#include "SHAL_TIMER_CALLBACK.h"
+
+void registerTimerCallback(Timer_Key key, TimerCallback callback){
+    timer_callbacks[static_cast<int>(key)] = callback;
+}