So there is a directional arrow, but, again the force on the front is reversed, and so must the rotation be when used as a front tire. The arrow indicates correct orientation to prevent overlap section tears.
When applied as a front tire the force is now backwards, so if the tire we're in the direction of the arrow, it could/would split the tire open.
So yes, an arrow, but it doesn't matter.
Not saying it's a 100% best practice, however, it's been done for literally 50+ years like this and, in fact, many tires are specifically designated to be a rear or flipped and run on the front.
The manufacturer is only going to designate tire specs up to the target market. So they will never explicitly say a 150/70 can be used in both positions, because, really the Rocket is like the only bike that uses a 150 tire on the front I'm aware or.
In similar fashion, there is no W rated 240/50R16, manufacturers are designing for the application, which is, a bike that tops out at 125mph in stock trim, so a V rating is more than enough.