feat(kez-chat/web): SW auto-reload on deploy + visible build sha in footer

Two related changes — both aimed at "can you tell what's deployed?"

1. SW auto-update (no more "refresh twice")

   The default vite-plugin-pwa autoUpdate behavior was: new SW
   downloads on first reload, activates on second reload. Users
   refresh after a deploy, still see old bundle, get confused.

   Now:
   • workbox: skipWaiting + clientsClaim → new SW activates and
     takes control of existing pages immediately on install.
   • main.ts listens for `controllerchange` and calls reload() once.
     New SW takes over → page reloads → new bundle loads.

   Net: deploys land on the FIRST refresh after the new bundle is
   reachable. (Caveat: the SW that's currently running has to
   download the new SW first, so the very first refresh after a
   deploy may serve stale + then auto-reload a beat later.)

2. Visible build sha in the footer

   vite.config.ts now runs `git rev-parse --short HEAD` at build
   time and injects __BUILD_SHA__ + __BUILD_TIME__ via Vite's
   `define`. App.svelte's footer renders the sha as a small monospace
   chip linking to the commit on gitea, with the build time on
   hover.

   "kez-chat web v0.1" → "kez-chat  [abc1234]  · source"

   So when you refresh and the chip changes value, you know the new
   build landed. When it doesn't, you know the SW is still serving
   the old bundle.

3. Killed the `apple-mobile-web-app-capable` deprecation warning by
   adding the standard `mobile-web-app-capable` next to it.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

kez-chat/web/index.html

@@ -13,6 +13,9 @@
 
   <!-- iOS Add-to-Home-Screen icon + status-bar styling -->
   <link rel="apple-touch-icon" href="/apple-touch-icon-180x180.png" />
+  <!-- mobile-web-app-capable is the standard; apple-mobile-web-app-capable
+       is the legacy iOS-only variant (Chrome flags it as deprecated). -->
+  <meta name="mobile-web-app-capable" content="yes" />
   <meta name="apple-mobile-web-app-capable" content="yes" />
   <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent" />
   <meta name="apple-mobile-web-app-title" content="kez-chat" />

kez-chat/web/src/App.svelte

@@ -66,8 +66,18 @@
 </main>
 
 <footer class="border-t border-gray-200 bg-white mt-16">
-  <div class="max-w-3xl mx-auto px-6 py-4 text-xs text-gray-500">
-    kez-chat web v0.1 ·
+  <div class="max-w-3xl mx-auto px-6 py-4 text-xs text-gray-500 flex items-center gap-2 flex-wrap">
+    <span>kez-chat web</span>
+    <a
+      href={`https://git.ptud.biz/DukeInc/Kez/commit/${__BUILD_SHA__}`}
+      target="_blank"
+      rel="noopener"
+      class="font-mono px-1.5 py-0.5 rounded bg-gray-100 text-gray-700 hover:bg-gray-200 no-underline"
+      title={`built ${__BUILD_TIME__}`}
+    >
+      {__BUILD_SHA__}
+    </a>
+    <span>·</span>
     <a
       href="https://git.ptud.biz/DukeInc/Kez"
       target="_blank"

kez-chat/web/src/app.d.ts

@@ -8,3 +8,7 @@ interface ImportMetaEnv {
 interface ImportMeta {
   readonly env: ImportMetaEnv;
 }
+
+// Vite `define` injects these at build time (see vite.config.ts).
+declare const __BUILD_SHA__: string;
+declare const __BUILD_TIME__: string;

kez-chat/web/src/main.ts

@@ -6,4 +6,22 @@ const app = mount(App, {
   target: document.getElementById("app")!,
 });
 
+// Force-reload when a freshly-installed service worker takes over.
+//
+// Default vite-plugin-pwa behavior is "next reload picks up the new
+// bundle" — fine, but means users have to refresh twice after a deploy.
+// With workbox skipWaiting + clientsClaim set (see vite.config.ts), the
+// new SW activates immediately and emits `controllerchange`; reloading
+// here means deploys land in users' browsers on the first refresh after
+// the SW finishes downloading. The `refreshing` guard avoids reload
+// loops if something weird happens.
+if ("serviceWorker" in navigator) {
+  let refreshing = false;
+  navigator.serviceWorker.addEventListener("controllerchange", () => {
+    if (refreshing) return;
+    refreshing = true;
+    window.location.reload();
+  });
+}
+
 export default app;

kez-chat/web/vite.config.ts

@@ -1,9 +1,26 @@
+import { execSync } from "node:child_process";
 import { defineConfig } from "vite";
 import { svelte } from "@sveltejs/vite-plugin-svelte";
 import tailwindcss from "@tailwindcss/vite";
 import { VitePWA } from "vite-plugin-pwa";
 
+// Build-time identity: short git SHA + ISO date. Surfaced in the footer
+// as "kez-chat <sha>" so users can eyeball which build they're on (handy
+// when verifying that a deploy actually landed instead of being cached).
+const BUILD_SHA = (() => {
+  try {
+    return execSync("git rev-parse --short HEAD").toString().trim();
+  } catch {
+    return "dev";
+  }
+})();
+const BUILD_TIME = new Date().toISOString();
+
 export default defineConfig({
+  define: {
+    __BUILD_SHA__: JSON.stringify(BUILD_SHA),
+    __BUILD_TIME__: JSON.stringify(BUILD_TIME),
+  },
   plugins: [
     svelte(),
     tailwindcss(),
@@ -37,6 +54,12 @@ export default defineConfig({
         ],
       },
       workbox: {
+        // Activate new SW immediately + take control of existing pages
+        // without waiting for them to close. Paired with the
+        // controllerchange reload in main.ts, this means deploys land
+        // on the first refresh instead of the second.
+        skipWaiting: true,
+        clientsClaim: true,
         // Precache the SPA shell. Chat data is fetched live from /v1/*
         // and we DON'T want it cached — see runtimeCaching below.
         globPatterns: ["**/*.{js,css,html,svg,png,ico,wasm}"],