Sync faces and the catalog before thumbnails, so a fresh device sees its names and collections first

The thumbnail stage ran first and, on a device that had just adopted its
peers' shards, spent its time re-uploading hundreds of megabytes under its
own client id while faces, people, collections and dates waited behind it.
Faces go first — the catalog merge assigns identities to faces this device
holds — then the catalog, then thumbnails.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

ui/dr-ui/src/derived_sync.rs

@@ -198,9 +198,13 @@ async fn run(
     // cheaper than probing, and an existing folder is not an error.
     let _ = backend.create_dir(&base).await;
 
-    let _ = tx.send(SyncMessage::Status("checking thumbnails…".into()));
-    sync_shards(backend, &base, thumbs_dir, scratch, &mut report).await?;
-
+    // Small before large, and what the user is waiting for before what
+    // fills in behind them. Faces first because the catalog merge assigns
+    // identities to faces this device holds, so they must be here by then;
+    // the catalog next for collections, people and dates; thumbnails last,
+    // because a fresh device's thumbnail stage is hundreds of megabytes and
+    // everything queued behind it — the sidebar, the timeline, the names —
+    // was invisible for as long as it ran.
     let _ = tx.send(SyncMessage::Status("checking faces…".into()));
     sync_face_shards(
         backend,
@@ -216,6 +220,9 @@ async fn run(
     let _ = tx.send(SyncMessage::Status("checking collections…".into()));
     sync_catalog(backend, &base, catalog_path, scratch, &mut report).await?;
 
+    let _ = tx.send(SyncMessage::Status("checking thumbnails…".into()));
+    sync_shards(backend, &base, thumbs_dir, scratch, &mut report).await?;
+
     // TRACES: FR-UI-8
     // Last, and it costs one small GET plus at most one small PUT. Last because
     // it is the only thing here that is not derived state and so the only thing