Recents: Add UMD Video discs played in the XMB

Picking one boots vshmain.prx with the disc mounted, and only the file booted went into Recents
(minus vshmain.prx itself), so the disc never did.

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

Core/System.cpp

@@ -663,6 +663,10 @@ static bool CPU_Init(FileLoader *fileLoader, IdentifiedFileType type, std::strin
 
 	if (g_CoreParameter.updateRecent) {
 		g_recentFiles.Add(g_CoreParameter.fileToStart.ToString());
+		// A UMD Video disc picked from the game list boots the XMB (which Add skips) to play it.
+		if (!g_CoreParameter.mountIso.empty() && g_CoreParameter.umdAutoboot.has_value()) {
+			g_recentFiles.Add(g_CoreParameter.mountIso.ToString());
+		}
 	}
 
 	// Update things that depend on game-specific config here.