bug: App Store `Launch` button doesn't play nice with new homepage

[nick1udwig]

When user clicks Launch, the app opens (good) but it doesn't open in a new "window"/iframe and instead "takes over" the App Store "window"/iframe (bad)

Make it so that clicking Launch opens a new iframe, just like clicking the app icon on the homepage would

[0x70b1a5]

also, node homepage has too dark bg on lightmode.

[nick1udwig]

done in #840