All rooms with names starting with 'call-' are now treated as
global rooms by the federation pipeline. This enables relay-
mediated media fallback for cross-relay direct calls: when Alice
on Relay A and Bob on Relay B both join the same call-<id> room,
the federation media forwarding pipeline (GlobalRoomActive
announcements + datagram forwarding + presence replication)
kicks in automatically without any runtime registration step.
Previously, cross-relay direct calls that couldn't go P2P
(symmetric NAT on either side) failed with "no media path"
because the call-<id> room wasn't in the configured global_rooms
set and media datagrams weren't forwarded across the federation
link.
The relay's existing ACL for call-* rooms (only the two
authorized fingerprints from the call registry can join)
prevents random clients from creating or eavesdropping on
call rooms.
## Changes
### `is_global_room` (federation.rs)
Added `room.starts_with("call-")` check before the static
global_rooms set lookup. Returns true immediately for any
call-prefixed room.
### `resolve_global_room` (federation.rs)
Return type changed from `Option<&str>` to `Option<String>`
(owned) because call-* room names aren't stored on `self` —
they come from the caller and resolve to themselves as the
canonical name. The 13 callers continue to work via String/&str
auto-deref; 4 HashMap lookups needed explicit `.as_str()` or
`&` borrows.
Full workspace test: 423 passing (no regressions).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
6cd61fc63b