fix: PWA manifest was never linked, icons 404'd; add install prompt (v0.64.0)

layout.tsx pointed <link rel="manifest"> at /manifest.json, but the
actual generated route (app/manifest.ts) serves at
/manifest.webmanifest -- the manifest was silently never picked up.
Its icons also referenced icon-192.png/icon-512.png, which don't
exist (only the .svg versions do). Both together meant Chrome/Android
install eligibility was broken with no visible error.

Also adds apple-mobile-web-app meta tags + viewport-fit=cover for
iOS home-screen installs, and a dismissible install banner driven by
the standard beforeinstallprompt event (Chromium-only by spec).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -2,6 +2,15 @@
 
 All notable changes to Epicure are documented here. This file is mirrored in-app at `/changelog` (and in the admin dashboard) via `apps/web/lib/changelog.ts` — update both together.
 
+## 0.64.0 — 2026-07-21 00:30
+
+### Fixed
+- The web app manifest was never actually linked into the page (pointed at `/manifest.json`, but the real route is `/manifest.webmanifest`) and its icons referenced PNGs that don't exist in the repo — both silently broke install eligibility on Chrome/Android. Manifest now links correctly and icons point at the existing SVGs.
+
+### Added
+- Added apple-mobile-web-app meta tags and a `viewport-fit=cover` safe-area setting for iOS home-screen installs.
+- Added an install-app banner (Chrome/Edge/Android only, via the standard `beforeinstallprompt` event) so the PWA install prompt is a first-class, dismissible UI element instead of relying on the browser's own icon.
+
 ## 0.63.0 — 2026-07-21 00:15
 
 ### Added