Unfortunately, neither of those is currently possible with the API. The API doesn't get an event on selection of a token, and even if it did, it can't trigger the opening of a character sheet or handout. The closest you can get is the Token Action bar for the selected token (which does open on selection). I think you could write an API that would preload a character's abilities with references to select character sheet buttons, though you might need to do some manual work to make that possible.