fix: persister l'état du Pomodoro Timer avec localStorage

- Sauvegarder l'état du timer (mode, temps restant, état running, sessions) dans localStorage
- Restaurer l'état au montage du composant
- Le timer ne se réinitialise plus quand le modal se ferme et se rouvre
- Simplifier le PomodoroModal pour utiliser children directement

src/components/PomodoroModal.tsx

@@ -1,18 +1,18 @@
+import { ReactNode } from "react";
 import {
   Dialog,
   DialogContent,
   DialogHeader,
   DialogTitle,
 } from "@/components/ui/dialog";
-import { PomodoroTimer } from "./PomodoroTimer";
 
 interface PomodoroModalProps {
   open: boolean;
   onOpenChange: (open: boolean) => void;
-  onTimerStateChange?: (isRunning: boolean, timeLeft: number, mode: string) => void;
+  children: ReactNode;
 }
 
-export function PomodoroModal({ open, onOpenChange, onTimerStateChange }: PomodoroModalProps) {
+export function PomodoroModal({ open, onOpenChange, children }: PomodoroModalProps) {
   return (
     <Dialog open={open} onOpenChange={onOpenChange}>
       <DialogContent className="max-w-md">
@@ -20,7 +20,7 @@ export function PomodoroModal({ open, onOpenChange, onTimerStateChange }: Pomodo
           <DialogTitle className="text-2xl">Pomodoro Timer</DialogTitle>
         </DialogHeader>
         <div className="mt-4">
-          <PomodoroTimer onStateChange={onTimerStateChange} />
+          {children}
         </div>
       </DialogContent>
     </Dialog>