fix(profile): force Stripe sync on mount + on window focus

Problem reported: user cancelled their subscription via the generic
'Gérer' portal, but the backend still showed the old subscription.
Root cause: stripe listen wasn't running, so the
customer.subscription.updated webhook never reached the server. The
Profile page was only reading from the DB (getSubscription), so it
stayed stale forever.

Fix: call stripeService.syncSubscription() alongside getSubscription()
at mount time. The fast DB read still happens first (instant display),
then the Stripe API call updates the state if anything has drifted.
Also add a window.addEventListener('focus', ...) listener that re-syncs
every time the user tabs back to the app — handles the common pattern
of opening Stripe portal in a new tab, doing something, then coming
back.

This makes the Profile self-healing even without a webhook setup in dev.
Production should still run the webhook for other apps/users, but this
fallback ensures individual users see the truth on their next visit.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/pages/Profile.tsx

@@ -128,8 +128,34 @@ export default function Profile() {
         const recipes = await recipeService.getRecipes();
         setUserRecipes(recipes);
 
-        // Charge aussi l'état d'abonnement (non-bloquant)
+        // État d'abonnement en 2 temps (ambos non-bloquants) :
-        stripeService.getSubscription().then(setSubscription).catch(() => {/* ignore */});
+        //  1. Lecture rapide depuis la DB (affichage immédiat)
+        //  2. Sync authoritative avec Stripe en arrière-plan. Garantit que
+        //     l'UI reflète l'état réel même si un webhook a été raté
+        //     (ex : stripe listen pas démarré en dev).
+        stripeService
+          .getSubscription()
+          .then(setSubscription)
+          .catch(() => {/* ignore */});
+
+        stripeService
+          .syncSubscription()
+          .then((synced) => {
+            setSubscription((prev) => {
+              // Ne met à jour que si quelque chose a vraiment changé,
+              // pour éviter un flash de re-render
+              if (
+                !prev ||
+                prev.plan !== synced.plan ||
+                prev.status !== synced.status ||
+                prev.hasActiveSubscription !== synced.hasActiveSubscription
+              ) {
+                return synced;
+              }
+              return prev;
+            });
+          })
+          .catch(() => {/* ignore */});
       } catch (err) {
         console.error("Erreur lors du chargement du profil:", err);
         setError("Impossible de charger les données du profil");
@@ -151,6 +177,21 @@ export default function Profile() {
     return () => clearTimeout(id);
   }, [success]);
 
+  // Resync l'abonnement quand l'utilisateur revient sur l'onglet. Gère
+  // le cas classique : ouvre Stripe portal dans un nouvel onglet, annule,
+  // ferme l'onglet, revient sur l'app → on veut refléter l'annulation
+  // immédiatement.
+  useEffect(() => {
+    const onFocus = () => {
+      stripeService
+        .syncSubscription()
+        .then(setSubscription)
+        .catch(() => {/* ignore */});
+    };
+    window.addEventListener("focus", onFocus);
+    return () => window.removeEventListener("focus", onFocus);
+  }, []);
+
   // --- Handlers ---
 
   const handleProfileSubmit = async (e: React.FormEvent) => {