Reload Npgsql types after migrations

src/Flashsharp/Data/Migrator.cs

@@ -46,6 +46,8 @@ public static class Migrator
         {
             await connection.ExecuteAsync("select pg_advisory_unlock(hashtext(@name))", new { name = LockName });
         }
+
+        await db.DataSource.ReloadTypesAsync(cancellationToken);
     }
 
     static IEnumerable<(string Version, string Sql)> LoadMigrations()