fix: silent relay state drift when activity bus drops events

backend/src/infra.rs

@@ -93,7 +93,7 @@ impl Infra {
             return Ok(());
         };
 
-        let is_new = self.relay_sync_is_new(&relay).await?;
+        let is_new = relay.synced == 0;
         self.sync_and_report(&relay, is_new).await;
 
         Ok(())
@@ -110,7 +110,7 @@ impl Infra {
 
         for relay in relays {
             if relay.sync_error.trim().is_empty() {
-                let is_new = self.relay_sync_is_new(&relay).await?;
+                let is_new = relay.synced == 0;
                 self.sync_and_report(&relay, is_new).await;
             } else {
                 self.schedule_relay_sync_retry(&relay.id, source).await?;
@@ -166,20 +166,11 @@ impl Infra {
             return Ok(());
         }
 
-        let is_new = self.relay_sync_is_new(&relay).await?;
+        let is_new = relay.synced == 0;
         self.sync_and_report(&relay, is_new).await;
         Ok(())
     }
 
-    async fn relay_sync_is_new(&self, relay: &Relay) -> Result<bool> {
-        if relay.synced == 1 {
-            return Ok(false);
-        }
-
-        let has_completed_sync = self.query.relay_has_completed_sync(&relay.id).await?;
-        Ok(!has_completed_sync)
-    }
-
     async fn sync_and_report(&self, relay: &Relay, is_new: bool) {
         match self.sync_relay(relay, is_new).await {
             Ok(()) => {

backend/src/query.rs

@@ -194,20 +194,4 @@ impl Query {
         .await?;
         Ok(rows)
     }
-
-    pub async fn relay_has_completed_sync(&self, relay_id: &str) -> Result<bool> {
-        let found = sqlx::query_scalar::<_, i64>(
-            "SELECT 1
-             FROM activity
-             WHERE resource_type = 'relay'
-               AND resource_id = ?
-               AND activity_type = 'complete_relay_sync'
-             LIMIT 1",
-        )
-        .bind(relay_id)
-        .fetch_optional(&self.pool)
-        .await?;
-
-        Ok(found.is_some())
-    }
 }