Web Push: goal, kickoff and full-time alerts for a followed team

Fully progressive: without VAPID keys in the environment the API says
404, the bell never renders, and the service worker addition (a push
handler via workbox importScripts — no SW strategy change) is inert.
With keys: a bell on each team page requests permission, subscribes
(one team per device) and the server diffs fixture states on every
broadcast to push Kickoff / Goal / Full time to that team's followers.
Dead endpoints (404/410) self-clean. Round-trip verified locally with
dev VAPID keys; disabled mode verified too.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

package.json

@@ -24,6 +24,7 @@
   },
   "dependencies": {
     "@tanstack/react-router": "^1.95.0",
+    "@types/web-push": "^3.6.4",
     "clsx": "^2.1.1",
     "d3-scale": "^4.0.2",
     "lucide-react": "^1.17.0",
@@ -31,6 +32,7 @@
     "react-dom": "^19.0.0",
     "recharts": "^2.15.0",
     "tailwind-merge": "^2.6.0",
+    "web-push": "^3.6.7",
     "zod": "^3.24.1",
     "zustand": "^5.0.2"
   },