VSH: Insert and eject UMDs from the pause screen

While the XMB is running, the pause screen offers "Insert UMD" with the
drive empty, opening the Switch UMD game picker, and "Eject UMD" with a disc
in. The XMB notices the change through its drive callback, as it does over
the debugger's game.umd.insert/eject. Games keep "Switch UMD".

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Core/HLE/sceKernelModule.cpp

@@ -542,6 +542,10 @@ u32 KernelFindModuleImport(const char *moduleName, const char *libraryName, u32
 // than a game), and reset on the next __KernelLoadExec. See ShouldHLEModuleForLoad below.
 static bool g_runningVSH = false;
 
+bool __KernelIsRunningVSH() {
+	return g_runningVSH;
+}
+
 // A sceKernelLoadModule whose caller is waiting for the file to be read. The module is only put
 // in memory when the wait ends - see sceKernelLoadModule.
 struct PendingModuleLoad {