Remove use of deprecated 'Role' type

Previously the 'Role' type was introduced as an `enum`, however, it has recently been deprecated in favor of using the `string` type. This way we can dynamically pull roles from the data on nightly deploys even though we have not updated the website to support those types.

- [ ] Remove the deprecated 'Role' type
- [ ] Convert the `RoleFilter` component to use a dynamic list of roles derived from the list of gods

Locate the deprecated Role definition and the RoleFilter component, then trace the list of gods used by the filter. Remove the enum-based type and make the filter derive its role options from that gods list; done means roles can change with nightly data without updating the website types.

Written by the indexing model from the issue text.