Drop the migration from the older folder

Nothing has shipped, so there is nothing to migrate: the program makes
Documents/N1MM Logger+ and starts there.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RoGtneMQaz4M9w7Kk49AVD

src/Nonemm.App/App.axaml.cs

@@ -18,7 +18,6 @@ public partial class App : Application
         {
             UserPaths paths = UserPaths.Default();
             paths.CreateFolders();
-            paths.AdoptOlderFiles();
             Settings settings = Settings.Load(paths.SettingsFile);
             Themes.Use(settings.Theme);
             Themes.Changed += (_, _) => ApplyTheme();