fix: recover stale service worker clients

wrnexus.config.ts

@@ -1,6 +1,9 @@
 import type { AppConfig } from "@wrnexus/styles";
 
 const config: AppConfig = {
+  // Repair clients that are still controlled by an older cached service worker.
+  // This can be removed after every preview client has advanced beyond v3.
+  head: '<script src="/pwa-recover.js" defer></script>',
   mobile: {
     enabled: true,
     appId: "com.example.wrnexusjs",
@@ -15,7 +18,7 @@ const config: AppConfig = {
   pwa: {
     name: "WRNexusJS Documentation",
     shortName: "WRNexusJS Docs",
-    cacheName: "wrnexus-pwa-v2",
+    cacheName: "wrnexus-pwa-v3",
     runtimeCaching: [
       {
         pattern: "^https://wrnexusjs\\.dev/",