feat: Implement new React frontend with authentication, add user and auth routes, and introduce various database migration and timezone diagnostic scripts.

src/pages/Index.tsx

@@ -15,7 +15,7 @@ import { Command, CommandEmpty, CommandGroup, CommandInput, CommandItem, Command
 import { RichTextEditor } from "@/components/RichTextEditor";
 import {
   PlusCircle, Search, User, LogOut, Settings, ChevronDown, Plus, Archive, Trash2,
-  Image as ImageIcon, CheckSquare, FileText, Rss, ExternalLink, RefreshCw, Key, Zap, Paperclip, X, Edit, Calendar as CalendarIcon, Tag as TagIcon, MessageSquare, Send, Check, ChevronsUpDown, Star
+  Image as ImageIcon, CheckSquare, FileText, Rss, ExternalLink, RefreshCw, Key, Zap, Paperclip, X, Edit, Calendar as CalendarIcon, Tag as TagIcon, MessageSquare, Send, Check, ChevronsUpDown, Star, Activity
 } from "lucide-react";
 import AuthService from "@/services/AuthService";
 import AdminService from "@/services/AdminService";
@@ -1617,6 +1617,7 @@ const Index = () => {
                             <span className="text-sm flex-1 leading-snug">
                               {todo.text}
                             </span>
+                            <Activity className="h-3.5 w-3.5 text-muted-foreground mr-1" title="En cours" />
                             <Button
                               variant="ghost"
                               size="icon"