Start an immediate observation

In the iOS 26 simulator the demo app would show a flash of missing content.

Author: groue

Documentation/DemoApps/GRDBDemo/GRDBDemo/Views/PlayerListModel.swift

@@ -56,7 +56,7 @@ import GRDB
 
         // Start observing the database.
         // Previous observation, if any, is cancelled.
-        cancellable = observation.start(in: appDatabase.reader) { error in
+        cancellable = observation.start(in: appDatabase.reader, scheduling: .immediate) { error in
             // Handle error
         } onChange: { [unowned self] players in
             self.players = players