fix: use job-specific sparse transfer progress

src/archive_clients/syncthing.py

@@ -192,11 +192,19 @@ class SyncthingTransferObserver:
                 for relative_path, expected_bytes in declared_files
             )
             observed_fraction = observed_bytes / total if total else 1.0
-            # Folder completion remains useful when Syncthing has already
-            # atomically published a file but still reports it in its need
-            # queue; the allocated-byte estimate is needed for sparse temp
-            # files that are pre-sized before their blocks arrive.
-            fraction = min(observed_fraction, float(raw_fraction) / 100)
+            # ``/db/completion`` is folder-wide.  It can be near zero when a
+            # route contains a freshly-created item even though the tracked
+            # job's temporary payload has already received many blocks.  For
+            # an incomplete temporary file, its allocated blocks are the only
+            # job-specific signal, so do not cap them with that unrelated
+            # folder aggregate.  Once every declared file is atomically
+            # present, retain the completion value as a conservative guard
+            # until the need queue has caught up.
+            fraction = (
+                observed_fraction
+                if observed_fraction < 1.0
+                else min(1.0, float(raw_fraction) / 100)
+            )
             completed_bytes = int(total * fraction)
         if complete:
             fraction = 1.0