A space is only joinable/forwardable across federation when federation is enabled for it. Space owners/admins need a toggle.

What to do

• Add a per-space 'Allow federation' toggle in space settings, wired to the server's space federation flag.
• Reflect the current state and handle permission errors.

Acceptance

• Toggling federation for a space enables/disables remote joins and content fanout for it.

Server reference

• Space federation flag checks: space_federation_enabled / space_origin in src/db/federation.rs; migration migrations/027_federation.sql.

Server reference — accordserver branch claude/federated-servers-xlydlj.