Add client code for new custom pm commands, use them, fix pm race conditions

sysmodules/rosalina/include/pmdbgext.h

@@ -0,0 +1,10 @@
+// License for this file: ctrulib's license
+// Copyright AuroraWright, TuxSH 2019
+
+#pragma once
+
+#include <3ds/services/pmapp.h>
+
+Result PMDBG_GetCurrentAppTitleId(u64 *outTitleId);
+Result PMDBG_DebugNextApplicationByForce(void);
+Result PMDBG_LaunchTitleDebug(Handle *outDebug, const FS_ProgramInfo *programInfo, u32 launchFlags);