[Stretch Goal]: Add Ability to Identify a "Main Goal"

[titapa-punpun]

Ticket

As a youth, I want to be able to identify my main goal of the week, so that I can better focus on specific tasks, as well as better keep track of my progress.

Acceptance Criteria

Given I'm on the outcomes screen, when I "star" a task, then the task is considered my main goal and shows up on the pop-up window on the bottom left corner.