feat(workspace): add help page, folder drag and drop, pinned notes section, and clean up editor UX

frontend/src/App.tsx

@@ -11,6 +11,7 @@ import {
   ChevronDown,
   RotateCcw,
   Palette,
+  HelpCircle,
 } from 'lucide-react';
 import { AuthStatus, DashboardStats, SharedList, Thought, User } from './lib/types';
 import { api, clearToken, getToken, triggerHaptic } from './lib/api';
@@ -28,6 +29,7 @@ import { SharedListsView } from './features/lists/SharedListsView';
 import { SetupAndAuthView } from './features/auth/SetupAndAuthView';
 import { UserSettingsView } from './features/settings/UserSettingsView';
 import { AdminSettingsView } from './features/settings/AdminSettingsView';
+import { HelpView } from './features/help/HelpView';
 
 type ActiveTab =
   | 'triage'
@@ -35,7 +37,8 @@ type ActiveTab =
   | 'workspace'
   | 'lists'
   | 'user_settings'
-  | 'admin_settings';
+  | 'admin_settings'
+  | 'help';
 
 interface ErrorBoundaryState {
   hasError: boolean;
@@ -375,6 +378,20 @@ export const App: React.FC = () => {
                     <span>Kontoeinstellungen</span>
                   </button>
 
+                  <button
+                    onClick={() => {
+                      triggerHaptic(10);
+                      setShowProfileMenu(false);
+                      setActiveTab('help');
+                    }}
+                    className={`w-full px-3.5 py-2.5 text-left flex items-center gap-2.5 hover:bg-panel-elevated transition-colors ${
+                      activeTab === 'help' ? 'text-accent font-semibold' : 'text-main'
+                    }`}
+                  >
+                    <HelpCircle className="w-4 h-4 text-accent" />
+                    <span>Hilfe & Anleitung</span>
+                  </button>
+
                   {isStaff && (
                     <button
                       onClick={() => {
@@ -516,9 +533,14 @@ export const App: React.FC = () => {
               <WorkspaceView
                 initialDocId={selectedDocId}
                 onStatsChange={refreshAll}
+                onOpenHelp={() => setActiveTab('help')}
               />
             )}
 
+            {activeTab === 'help' && (
+              <HelpView onBack={() => setActiveTab('workspace')} />
+            )}
+
             {activeTab === 'lists' && (
               <SharedListsView onRefreshGlobal={refreshAll} />
             )}