pgl: Reimplement the pgl sysmodule (#896)

* pgl: add skeleton folder to stratosphere

* pgl: Add service interface for IShellInterface

* pgl: begin skeletoning shell service, implement two commands.

* pgl: Implement three more commands.

* pgl: implement bool tracking commands

* pgl: Implement TriggerApplicationSnapShotDumper

* pgl: implement InitializeProcessControlTask

* pgl: Implement pgl::srv::Initialize

* pgl: Implement main()

* pgl: Implement (Get)ShellEventObserver

* pgl: implement LaunchProgramFromHost, GetHostContentMetaInfo

* pgl: Implement ProcessControlTask

* settings: fix duplicate object name

* pgl: fix minor bugs in impl

libraries/libstratosphere/source/settings/settings_fwdbg_api.cpp

@@ -17,8 +17,11 @@
 
 namespace ams::settings::fwdbg {
 
-    /* TODO: Implement when libnx wrapper is added. */
-    bool IsDebugModeEnabled();
+    bool IsDebugModeEnabled() {
+        bool value = false;
+        R_ABORT_UNLESS(::setsysGetDebugModeFlag(std::addressof(value)));
+        return value;
+    }
 
     size_t WEAK_SYMBOL GetSettingsItemValueSize(const char *name, const char *key) {
         u64 size = 0;