Support project-wide Saved Searches

### Problem Statement

**Organization context**
In our organization, there are a lot of projects owned by different teams. All those teams have specific needs and workflows. Each team has a team leader. Sentry is managed by an Operation team which has Admin access. Team leaders have the user role.

**Our problem**
One of our problems is about the way roles are implemented in Sentry. Our team leaders need to create Saved Searches so developers can easily filter issues in their project. But in order to create Saved Searches, they need to have the manager role. Since the assignment of users to project is done by our Operation team, our team leaders have too much privileges. And pinning searches is not an option since it's only visible by the creator of the search. We follow a least-privilege policy in our tools and it would be great for specific users to be able to create saved searches without having the permission of adding and remove members from the organization or worse to gain admin access on all teams.

**Our duct-tape solution**
Team leaders have Manager role and we accept the risk but it is not ideal.

### Solution Brainstorm

I see 2 ways we could fix this issue:

1. Have a more granular way to create saved searches scoped in a project X instead of organization-wide. This feature could be enabled for each user in project X. That would allow for users to create Saved Searches by themselves in their project.
2. Custom roles. Pretty complex to implement I think but it would be epic. In our case I see a role we could call team-leader with the same permissions as a user but with the possibility to manage Saved Searches under their projects.

I hope my feature request is not too much confusing so don't hesitate if you want me to clarify some things.

Best Regards,
Richer