WK Autoloader Store Y2JB

• Keeps the Store tile's stock name and art.
• Repoints NPXS40047 at the installed YouTube app's own psgm:play deeplink.
• Detects PPSA01650 / PPSA01651 / PPSA01652; prefers the variant with download0.dat.
• Backs up app.db / appinfo.db to /data/autojb-store-only-backup/.
• Does not install or update Y2JB.