Brows tvOS app store online?

No, there isn't.

Nothing official from Apple but you might find this 3rd party site useful. http://www.slidetoplay.com/apple-tv-apps-top-list/

As given you cannot review the Apple TV app store in a web browser, or explore tvOS apps in iTunes, however this site scrapes the store to give access to the current chart listings with, as far as I can tell, no third-party advertising or influence: http://tvos.emil.click/.

If you think it would help to have a full web front end to the the Apple TV store you could suggest it at Apple TV Feedback.

tt2