fix(sync): schedule auxiliary coverage for full repositories

Priority demotion moved q-tagged and other non-essential repository references out of core live filters, but descendant maintenance selected only relays that already had root events. A full repository with no accepted roots therefore never installed its auxiliary repository coverage, breaking bounded-REQ and adaptive regrouping delivery.

Include relays with full repositories in the bounded maintenance frontier. Update the constrained-REQ regression to wait for the observable auxiliary generation before using a q-tagged event as its live-delivery probe.

State-only repositories remain excluded, and maintenance still advances only one selected relay per tick. Validated with the bounded-REQ and filter-count-refusal integration tests.

src/sync/mod.rs

@@ -4450,7 +4450,7 @@ impl SyncManager {
         let mut relay_urls: Vec<String> = targets
             .iter()
             .filter(|(relay_url, needs)| {
-                !needs.root_events.is_empty()
+                (!needs.repos.is_empty() || !needs.root_events.is_empty())
                     && states.get(*relay_url).is_some_and(|state| {
                         matches!(
                             state.connection_status,

tests/sync/live_sync.rs

@@ -150,6 +150,7 @@ async fn test_live_sync_batches_repo_filters_below_source_req_limit() {
     wait_for_sync_connection(syncing.url(), 1, Duration::from_secs(5))
         .await
         .expect("syncing relay should connect to constrained source");
+    wait_for_new_descendant_live_generation(&syncing, 0, Duration::from_secs(20)).await;
 
     // Observe one q-tagged event completing the round trip before testing a
     // second live event. This proves the relevant subscription is installed