Multitenancy

[corywatilo]

We have an issue with multitenancy where, if you're a member of one community, you can't also have your own community with the same email address.

Example:

1. User signs up to posthog.com community as a member
2. User tries to login/signup to Squeak! admin with same email

This doesn't work because they're a member of the posthog.com community as a user.

We need a way for people to use the same email for multiple communities.

Considerations

• When authing to Squeak! admin, a way to select a project you're an admin of. (I don't think you need to be able to login to Squeak! admin as only a user of someone else's community.)