feat(sync): broadcast synced events to WebSocket subscribers

Enable recursive relay discovery by broadcasting synced events to
WebSocket subscribers via LocalRelay.notify_event(). This allows the
SelfSubscriber to receive 30617 announcements synced from external
relays and discover additional relay URLs to connect to.

Changes:
- Pass LocalRelay to SyncManager::new() from main.rs
- Add local_relay field to SyncManager struct
- Call notify_event() after saving synced events to database
- Enable test_recursive_relay_discovery_syncs_announcement test

The test verifies that when relay_a syncs announcement_x from bootstrap
relay_b (which lists relay_c), relay_a discovers and connects to
relay_c to sync announcement_y.

Fixes recursive relay discovery from bootstrap sync.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/main.rs b/src/main.rs
index f887e42..31c7b63 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -58,6 +58,7 @@ async fn main() -> Result<()> {
             config.domain.clone(),
             relay_with_db.database.clone(),
             relay_with_db.write_policy.clone(),
+            relay_with_db.relay.clone(),
             &config,
         );