Serve the MealQuest favicon instead of the browser default (Maestro 7c778111)

index.html linked only the apple-touch-icon, so browsers fell back to a
default favicon. generate-icons now also writes favicon.ico (16/32/48
PNG-in-ICO) and 16/32 px PNG favicons from the v1 logo; index.html links
them, and the service worker precaches every icon and favicon so the
offline shell keeps them (the glob covers the manifest icons, so the
plugin no longer injects them a second time).

pwa.test.ts asserts the build ships the favicons at the right sizes,
links them from index.html, and precaches each icon exactly once.

Task: 7c778111-c615-4437-a3f6-0e36bcb97e63

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/pwa.test.ts

@@ -1,7 +1,8 @@
 // @vitest-environment node
 // Builds the app with the production config and serves the result, so the
 // assertions cover what ships in dist: the web manifest, the service worker,
-// every icon, and the service worker registration that only builds include.
+// every icon and favicon, and the service worker registration that only builds
+// include.
 import { afterAll, beforeAll, describe, expect, it } from 'vitest'
 import { build, createServer, preview, type PreviewServer, type ViteDevServer } from 'vite'
 import tokens from './styles/tokens.css?raw'
@@ -12,9 +13,13 @@ const icons = [
   { path: '/icons/icon-192.png', size: 192 },
   { path: '/icons/icon-512.png', size: 512 },
   { path: '/icons/icon-maskable-512.png', size: 512 },
+  { path: '/icons/favicon-16.png', size: 16 },
+  { path: '/icons/favicon-32.png', size: 32 },
   { path: '/apple-touch-icon.png', size: 180 },
 ]
 
+const faviconSizes = [16, 32, 48]
+
 function token(name: string): string {
   const value = tokens.match(new RegExp(`^\\s*${name}:\\s*([^;\\s]+);`, 'm'))?.[1]
   if (!value) throw new Error(`${name} is not defined in tokens.css`)
@@ -38,6 +43,18 @@ function pngSize(bytes: Uint8Array): { width: number; height: number } {
   return { width: view.getUint32(16), height: view.getUint32(20) }
 }
 
+// The images in an ICO file: a 6-byte header (reserved, type 1, count), then
+// a 16-byte directory entry per image giving its byte length and offset.
+function icoImages(bytes: Uint8Array): Uint8Array[] {
+  const view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength)
+  expect([view.getUint16(0, true), view.getUint16(2, true)]).toEqual([0, 1])
+  return Array.from({ length: view.getUint16(4, true) }, (_, i) => {
+    const entry = 6 + 16 * i
+    const offset = view.getUint32(entry + 12, true)
+    return bytes.subarray(offset, offset + view.getUint32(entry + 8, true))
+  })
+}
+
 describe('production build', () => {
   let server: PreviewServer
   let origin: string
@@ -94,13 +111,25 @@ describe('production build', () => {
     expect(pngSize(bytes)).toEqual({ width: size, height: size })
   })
 
+  it('ships /favicon.ico holding the logo as PNGs at every favicon size', async () => {
+    const bytes = new Uint8Array(await (await get('/favicon.ico')).arrayBuffer())
+    expect(icoImages(bytes).map((png) => pngSize(png))).toEqual(
+      faviconSizes.map((size) => ({ width: size, height: size })),
+    )
+  })
+
   it('emits sw.js with the precache list injected', async () => {
     const sw = await (await get('/sw.js')).text()
     expect(sw).not.toContain('self.__WB_MANIFEST')
     expect(sw).toContain('"url":"index.html"')
-    for (const { path } of icons.slice(0, 3)) {
-      expect(sw).toContain(`"url":"${path.slice(1)}"`)
+  })
+
+  it('precaches every icon and favicon so the offline shell keeps them', async () => {
+    const urls = precacheEntries(await (await get('/sw.js')).text()).map((entry) => entry.url)
+    for (const path of [...icons.map((icon) => icon.path), '/favicon.ico']) {
+      expect(urls).toContain(path.slice(1))
     }
+    expect(new Set(urls).size, 'precache URLs are unique').toBe(urls.length)
   })
 
   it('precaches the shell, JS, CSS and every self-hosted font', async () => {
@@ -129,6 +158,17 @@ describe('production build', () => {
     expect(html).toContain('<link rel="apple-touch-icon" href="/apple-touch-icon.png" />')
   })
 
+  it('links the favicons from index.html', async () => {
+    const html = await (await get('/')).text()
+    expect(html).toContain('<link rel="icon" href="/favicon.ico" sizes="16x16 32x32 48x48" />')
+    expect(html).toContain(
+      '<link rel="icon" type="image/png" sizes="32x32" href="/icons/favicon-32.png" />',
+    )
+    expect(html).toContain(
+      '<link rel="icon" type="image/png" sizes="16x16" href="/icons/favicon-16.png" />',
+    )
+  })
+
   it('registers /sw.js at scope / from index.html', async () => {
     const html = await (await get('/')).text()
     expect(html).toContain('<script id="vite-plugin-pwa:register-sw" src="/registerSW.js"></script>')