feat: auto-update PWA when new version available

Uses registerSW to detect new service worker versions and reload
automatically. Defers reload if file transfers are active, checking
every 30s until transfers complete.

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

web/src/main.tsx

@@ -1,9 +1,35 @@
 import { StrictMode } from "react";
 import { createRoot } from "react-dom/client";
 import { BrowserRouter } from "react-router-dom";
+import { registerSW } from "virtual:pwa-register";
 import App from "./App";
+import { useStore } from "./stores/useStore";
 import "./index.css";
 
+// Auto-reload when a new service worker is available
+const updateSW = registerSW({
+  onNeedRefresh() {
+    const hasActiveTransfers = useStore
+      .getState()
+      .transfers.some((t) => t.status === "transferring" || t.status === "pending");
+    if (hasActiveTransfers) {
+      // Defer update — check again every 30s
+      const interval = setInterval(() => {
+        const still = useStore
+          .getState()
+          .transfers.some((t) => t.status === "transferring" || t.status === "pending");
+        if (!still) {
+          clearInterval(interval);
+          updateSW(true);
+        }
+      }, 30_000);
+    } else {
+      updateSW(true);
+    }
+  },
+  onOfflineReady() {},
+});
+
 createRoot(document.getElementById("root")!).render(
   <StrictMode>
     <BrowserRouter>

web/tsconfig.json

@@ -3,7 +3,7 @@
   "compilerOptions": {
     "outDir": "./dist",
     "jsx": "react-jsx",
-    "types": ["vite/client"],
+    "types": ["vite/client", "vite-plugin-pwa/client"],
     "declaration": false,
     "declarationMap": false
   },