Currently a Power App that belongs to a Solution cannot trigger a Flow (the button for Flow is missing from the Actions tab in the Power Apps maker).
This means that Solution specific connectors like the Common Data Service (current environment) cannot be used in a Flow that is triggered by a Power App. Therefore, the AI Builder Predict action in a Flow cannot be triggered from a Power App.
It would be great to have Power Apps in Solutions to be able to trigger Flows in the same solution at least.
FYI @ZePowerDiver
Thanks for posting this idea @HSheild. You can now have canvas Power Apps in solutions trigger flows in the same solution.