feat(ui): nav app persistente nel masthead (desktop + drawer mobile)

L'utente non aveva modo di saltare da una pagina app all'altra senza tornare alla home (solo il logo era cliccabile). Aggiunta nav globale:

- **Desktop**: row di link orizzontale a destra del logo (Cucina · Tracking · Digiuno · Spesa · Profilo · Abbonamento). Pagina corrente evidenziata in pomodoro, hover sulle altre.
- **Mobile**: bottone hamburger (≡ Menu) che apre un drawer sotto la riga di header con le 6 voci. Si chiude da solo al cambio di pathname.

`<Masthead>` ora è un Client Component (serve usePathname). Prop `showNav` (default false) controlla la nav: attivata sulle 7 pagine logged-in (`/`, /plan, /tracking, /fasting, /shopping, /profile, /billing, /recipes/[id]). Lasciata off su welcome, onboarding, sign-in, sign-up.

Aggiunti i18n keys: navPlan/navTracking/navFasting/navShopping/navProfile/navBilling. Rimossi gli `issueLabel="N. XX — ..."" dalle pagine app (`issueLabel` resta supportato per pagine senza nav).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/messages/it.json

@@ -16,6 +16,12 @@
     "viewTracking": "Pesata & misure",
     "viewFasting": "Digiuno intermittente",
     "viewBilling": "Abbonamento & fatture",
+    "navPlan": "Cucina",
+    "navTracking": "Tracking",
+    "navFasting": "Digiuno",
+    "navShopping": "Spesa",
+    "navProfile": "Profilo",
+    "navBilling": "Abbonamento",
     "lettura": "Continua la lettura",
     "inizia": "Inizia",
     "greeting": "Buongiorno, <name>{name}</name>.",

apps/web/src/app/[locale]/billing/page.tsx

@@ -39,7 +39,7 @@ function BillingPageContent({ status }: { status: BillingStatus | null }) {
     return (
       <div className="relative">
         <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-          <Masthead issueLabel="N. 08 — Abbonamento" />
+          <Masthead showNav />
           <main className="pb-24 pt-12">
             <p className="editorial-eyebrow">{t('errorLoading')}</p>
           </main>
@@ -54,7 +54,7 @@ function BillingPageContent({ status }: { status: BillingStatus | null }) {
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead issueLabel="N. 08 — Abbonamento" />
+        <Masthead showNav />
         <main className="relative overflow-hidden pb-24 pt-10 sm:pt-12">
           <CursorGlow color="hsl(var(--oro))" size={520} />
           <div

apps/web/src/app/[locale]/fasting/page.tsx

@@ -44,7 +44,7 @@ function FastingPageContent({
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead issueLabel="N. 07 — Digiuno" />
+        <Masthead showNav />
         <main className="relative overflow-hidden pb-24 pt-10 sm:pt-12">
           <CursorGlow color="hsl(var(--pomodoro))" size={520} />
           <div

apps/web/src/app/[locale]/page.tsx

@@ -28,7 +28,7 @@ function HomeContent({
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead />
+        <Masthead showNav={!!userName} />
         {userName ? (
           <SignedInDashboard userName={userName} billing={billing} />
         ) : (

apps/web/src/app/[locale]/plan/page.tsx

@@ -64,7 +64,7 @@ function PlanPageContent({
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead issueLabel="N. 05 — Cucina" />
+        <Masthead showNav />
         <main className="relative overflow-hidden py-10 sm:py-12">
           <CursorGlow color="hsl(var(--pomodoro))" size={520} />
           <div

apps/web/src/app/[locale]/profile/page.tsx

@@ -59,7 +59,7 @@ function ProfilePageContent({
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead issueLabel="N. 04 — Profilo" />
+        <Masthead showNav />
         <main className="relative overflow-hidden pb-24 pt-10 sm:pt-12">
           <CursorGlow color="hsl(var(--oliva))" size={520} />
           <div

apps/web/src/app/[locale]/recipes/[id]/page.tsx

@@ -111,7 +111,7 @@ function RecipeContent({ recipe }: { recipe: RecipeView }) {
 
   return (
     <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-      <Masthead issueLabel={`N. 08 — ${t(`categoryLabel.${recipe.category}`)}`} />
+      <Masthead showNav />
       <main className="py-10 sm:py-14">
         <Link
           href="/plan"

apps/web/src/app/[locale]/shopping/page.tsx

@@ -54,7 +54,7 @@ function ShoppingPageContent({ list }: { list: ShoppingList | null }) {
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead issueLabel="N. 09 — La spesa" />
+        <Masthead showNav />
         <main className="relative overflow-hidden pb-24 pt-10 sm:pt-12">
           <CursorGlow color="hsl(var(--oliva))" size={520} />
           <div

apps/web/src/app/[locale]/tracking/page.tsx

@@ -73,7 +73,7 @@ function TrackingPageContent({
   return (
     <div className="relative">
       <div className="min-h-screen w-full px-6 sm:px-10 lg:px-16 xl:px-24">
-        <Masthead issueLabel="N. 06 — Tracking" />
+        <Masthead showNav />
         <main className="relative overflow-hidden pb-24 pt-10 sm:pt-12">
           <CursorGlow color="hsl(var(--oro))" size={520} />
           <div

apps/web/src/components/masthead.tsx

@@ -1,33 +1,143 @@
+'use client';
+
 import Link from 'next/link';
+import { usePathname } from 'next/navigation';
+import { useTranslations } from 'next-intl';
+import { useEffect, useState } from 'react';
 
 import { cn } from '@/lib/utils';
 
 interface MastheadProps {
   /**
-   * Etichetta opzionale a destra (es. "N. 05 — Cucina"). Se omessa, l'header
-   * resta minimale con solo il logo a sinistra. Tono più \"app\" che \"magazine\".
+   * Etichetta opzionale a destra (es. "N. 05 — Cucina"). Mostrata solo
+   * quando la nav app non è attiva (auth pages, welcome, onboarding).
    */
   issueLabel?: string;
+  /**
+   * Mostra la nav app (Cucina/Tracking/Digiuno/Spesa/Profilo/Abbonamento).
+   * Da accendere su tutte le pagine logged-in dopo onboarding.
+   */
+  showNav?: boolean;
   className?: string;
 }
 
+interface NavEntry {
+  href: string;
+  key: 'navPlan' | 'navTracking' | 'navFasting' | 'navShopping' | 'navProfile' | 'navBilling';
+}
+
+const NAV: ReadonlyArray<NavEntry> = [
+  { href: '/plan', key: 'navPlan' },
+  { href: '/tracking', key: 'navTracking' },
+  { href: '/fasting', key: 'navFasting' },
+  { href: '/shopping', key: 'navShopping' },
+  { href: '/profile', key: 'navProfile' },
+  { href: '/billing', key: 'navBilling' },
+];
+
 /**
- * Top-of-page header minimale: logo a sinistra, sezione corrente a destra (se
- * fornita). Una riga sottile sotto fa da divider editoriale.
+ * Top-of-page header dell'app. Logo a sx, nav orizzontale al centro/destra
+ * (desktop) o hamburger drawer (mobile). Pagina corrente evidenziata in
+ * pomodoro. Una riga sottile sotto fa da divider editoriale.
  */
-export function Masthead({ issueLabel, className }: MastheadProps) {
+export function Masthead({ issueLabel, showNav = false, className }: MastheadProps) {
+  const t = useTranslations('Home');
+  const pathname = usePathname();
+  const [open, setOpen] = useState(false);
+
+  // Quando il pathname cambia, chiudi il drawer mobile (utente ha navigato).
+  useEffect(() => setOpen(false), [pathname]);
+
+  // Match di fallback: il pathname è tipo /it/plan, dobbiamo confrontare
+  // ignorando il segmento di locale. Usiamo `.includes('/plan')` con
+  // controllo che inizi con /<locale>/plan oppure /plan.
+  function isActive(href: string): boolean {
+    if (!pathname) return false;
+    // strip locale prefix se presente
+    const stripped = pathname.replace(/^\/[a-z]{2}(\/|$)/, '/');
+    if (href === '/') return stripped === '/';
+    return stripped.startsWith(href);
+  }
+
   return (
     <header className={cn('relative pb-5 pt-6', className)}>
-      <div className="flex items-center justify-between gap-4">
+      <div className="flex items-center justify-between gap-6">
         <Link
           href="/"
-          className="monogram tracking-tight transition-opacity hover:opacity-70"
+          className="monogram shrink-0 tracking-tight transition-opacity hover:opacity-70"
           aria-label="KetoPath"
         >
           KetoPath<span className="text-pomodoro">.</span>
         </Link>
-        {issueLabel ? <p className="editorial-eyebrow hidden sm:block">{issueLabel}</p> : null}
+
+        {showNav ? (
+          <>
+            {/* Desktop nav */}
+            <nav className="hidden items-baseline gap-7 md:flex">
+              {NAV.map((item) => {
+                const active = isActive(item.href);
+                return (
+                  <Link
+                    key={item.href}
+                    href={item.href}
+                    className={cn(
+                      'font-mono text-[11px] uppercase tracking-widest transition-colors',
+                      active ? 'text-pomodoro' : 'text-ink-soft hover:text-ink',
+                    )}
+                  >
+                    {t(item.key)}
+                  </Link>
+                );
+              })}
+            </nav>
+
+            {/* Mobile: hamburger button */}
+            <button
+              type="button"
+              onClick={() => setOpen((v) => !v)}
+              aria-expanded={open}
+              aria-label="Apri menu"
+              className="text-ink hover:text-pomodoro -mr-2 inline-flex items-center gap-2 p-2 font-mono text-[11px] uppercase tracking-widest transition-colors md:hidden"
+            >
+              <span aria-hidden className="text-base leading-none">
+                {open ? '×' : '≡'}
+              </span>
+              <span>Menu</span>
+            </button>
+          </>
+        ) : issueLabel ? (
+          <p className="editorial-eyebrow hidden sm:block">{issueLabel}</p>
+        ) : null}
       </div>
+
+      {/* Mobile drawer: appare sotto la riga di header */}
+      {showNav && open ? (
+        <nav
+          aria-label="Navigazione principale"
+          className="border-ink/15 bg-carta-light animate-fade-up mt-4 border-b border-t py-2 [animation-duration:200ms] md:hidden"
+        >
+          <ul className="flex flex-col">
+            {NAV.map((item) => {
+              const active = isActive(item.href);
+              return (
+                <li key={item.href}>
+                  <Link
+                    href={item.href}
+                    className={cn(
+                      'border-ink/10 flex items-center justify-between gap-4 border-b py-3 font-mono text-xs uppercase tracking-widest transition-colors last:border-b-0',
+                      active ? 'text-pomodoro' : 'text-ink hover:text-pomodoro',
+                    )}
+                  >
+                    {t(item.key)}
+                    <span aria-hidden>→</span>
+                  </Link>
+                </li>
+              );
+            })}
+          </ul>
+        </nav>
+      ) : null}
+
       <div className="rule mt-5" />
     </header>
   );