Homepage is scope-less, but lists (all) workspaces, which calls reverse('workspace:detail') without scope, linking workspaces from non-default scopes to the default scope. Proposal: split the current homepage into: * a list of scopes that goes in `/` * a list of workspaces that goes in `/scope/` (cf. !1187). Also filters the scopes that the current user has access to (depends on !1187/!1207/!1222). (report time in #395)