Offer project-level roles

### Problem Statement

Currently, a user's level of access to a project is determined by their team role: `Team Admin` or `Team Contributor`
So in a case where all teams have their members assigned the role `Team Admin`, the moment they have access to a project they will be granted admin actions on that project.

It would be practical to have a more granular setup, where a team can be member of a project A as a `Team Contributor` and a member of a project B as a `Team Admin`.

This allows for scenarios where teams want to give access to other teams to view their project metrics without giving them privileged access.

### Solution Brainstorm

- Offer `Project Admin` and `Project Contributor` roles.
- The creator of a project is assigned the role `Project Admin` and can add teams to the project and assign to them `Project Admin` or `Project Contributor`.

### Product Area

Settings - Projects