feat(web): PWA — manifest, icone, meta iOS

- src/app/manifest.ts (Next 14 file convention) → /manifest.webmanifest
- public/icons/icon.svg + icon-maskable.svg (vettoriali, palette editoriale)
- scripts/generate-icons.mjs (sharp): genera icon-192/512.png,
  apple-touch-icon-180.png, icon-maskable-512.png, badge-72.png
- layout.tsx: viewport con themeColor light/dark, manifest link,
  appleWebApp meta (capable + title), icons (svg + png + apple touch)
- .eslintrc: ignora scripts Node out-of-project; lint-staged: .mjs format-only

Display standalone, lang it, theme #221d18 (ink) / bg #f6f0df (carta).
Sblocca "Installa app" su Chrome/Edge/Android e "Aggiungi alla Home" su
iOS Safari — quest'ultimo è pre-requisito per ricevere le push su iOS.

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

package.json

@@ -47,11 +47,11 @@
     "@vitest/coverage-v8": "^1.6.0"
   },
   "lint-staged": {
-    "*.{ts,tsx,jsx,cjs,mjs}": [
+    "*.{ts,tsx,jsx,cjs}": [
       "eslint --fix --max-warnings=0",
       "prettier --write"
     ],
-    "*.js": [
+    "*.{js,mjs}": [
       "prettier --write"
     ],
     "*.{json,md,yml,yaml,css}": [