Add PWA support with pizza emoji icon

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: jmckible

app/views/layouts/application.html.haml

@@ -8,9 +8,18 @@
     = turbo_refreshes_with method: :morph, scroll: :preserve
     = stylesheet_link_tag 'application', 'data-turbolinks-track': 'reload'
     = javascript_importmap_tags
-    /= favicon_link_tag "favicons/#{Time.zone.now.mday}.png"
+    %link{ rel: 'icon', href: '/icon.svg', type: 'image/svg+xml' }
     %meta{ charset: 'utf8' }
     %meta{ name: 'viewport', content: 'width=device-width, initial-scale=1, shrink-to-fit=no' }
+    %meta{ name: 'theme-color', content: '#61afef' }
+    %meta{ name: 'apple-mobile-web-app-capable', content: 'yes' }
+    %meta{ name: 'apple-mobile-web-app-status-bar-style', content: 'default' }
+    %link{ rel: 'manifest', href: '/manifest.json' }
+    %link{ rel: 'apple-touch-icon', href: '/icon.png' }
+    :javascript
+      if ("serviceWorker" in navigator) {
+        navigator.serviceWorker.register("/service-worker.js")
+      }
 
 
   %body

public/apple-touch-icon-precomposed.png

@@ -0,0 +1,21 @@
+{
+  "name": "Esophagus",
+  "short_name": "Esophagus",
+  "start_url": "/",
+  "display": "standalone",
+  "background_color": "#fafafa",
+  "theme_color": "#61afef",
+  "icons": [
+    {
+      "src": "/icon.svg",
+      "sizes": "any",
+      "type": "image/svg+xml",
+      "purpose": "any"
+    },
+    {
+      "src": "/icon.png",
+      "sizes": "512x512",
+      "type": "image/png"
+    }
+  ]
+}

public/apple-touch-icon.png

@@ -0,0 +1,16 @@
+// Minimal service worker to enable PWA install prompt.
+// Network-first strategy — the app relies on Turbo for navigation.
+self.addEventListener("install", (event) => {
+  self.skipWaiting()
+})
+
+self.addEventListener("activate", (event) => {
+  event.waitUntil(clients.claim())
+})
+
+self.addEventListener("fetch", (event) => {
+  // Let the browser handle all fetches normally (network-first).
+  // This satisfies the PWA installability requirement without
+  // introducing caching complexity.
+  return
+})