feat: add kernel ACPI support for querying battery percentage, add battery indicator to desktop, move log state to 0:/state directory

kernel/src/Boot/Main.cpp

@@ -25,6 +25,8 @@
 #include <ACPI/CpuIdle.hpp>
 #include <ACPI/AcpiShutdown.hpp>
 #include <ACPI/AcpiEvents.hpp>
+#include <ACPI/EmbeddedController.hpp>
+#include <ACPI/Battery.hpp>
 #include <Hal/Apic/ApicInit.hpp>
 #include <Pci/Pci.hpp>
 #include <Timekeeping/ApicTimer.hpp>
@@ -131,6 +133,12 @@ extern "C" void kmain() {
 #if defined (__x86_64__)
     if (g_acpi.GetXSDT() != nullptr) {
         Hal::AcpiShutdown::Initialize(g_acpi.GetXSDT());
+
+        // The EC is the transport behind battery (and most thermal) methods, so
+        // it has to be latched before anything evaluates them.
+        Hal::EmbeddedController::Initialize(g_acpi.GetXSDT());
+        Hal::Battery::Initialize();
+
         Hal::CpuIdle::Initialize(g_acpi.GetXSDT());
 
         Hal::ApicInitialize(g_acpi.GetXSDT());