feat(ui): streamline workspace settings and remove sharing

Unify compact workspace controls and panel transitions, move directory actions into the context menu, and remove backlink UI.

Reorganize settings with searchable sections, per-setting resets, shortcut search, and accurate save feedback.

Remove sharing UI, APIs, authentication helpers, and storage code; provide a transactional cleanup script with retirement tests. Reject directories during orphan image cleanup and cover mixed-batch preservation.

cmd/rawmark/main.go

@@ -83,7 +83,6 @@ func run(addr string) error {
 	srv := api.New(v, am, st, hub, idx)
 	srv.ThemesDir = filepath.Join(dataDir, "themes")
 	srv.PluginsDir = filepath.Join(dataDir, "plugins")
-	go srv.FollowMoves(ctx)
 	httpServer := &http.Server{
 		Addr:              addr,
 		Handler:           srv.Handler(web.Dist()),