fix: bw/stats 404, gateway links, history crash

- swr.ts: remove useBandwidth(), drop bw from useDashboard()
- events/route.ts: skip bandwidth SSE (Kubo 0.28.0 unsupported)
- usage/page.tsx: remove getBWStats call + bw references
- helpers.ts: gatewayLink -> ipfs.maos.dedyn.io (subdomain only)
- upload/page.tsx: fix local gatewayLink (subdomain only)
- storage.ts: update default gatewayUrl, add defensive getHistory()

package.json

@@ -5,6 +5,7 @@
   "description": "IPFS Portal — Next.js frontend for remote IPFS node management",
   "scripts": {
     "dev": "next dev --port 3445",
+    "dev:webpack": "next dev --port 3445 --webpack",
     "build": "next build",
     "export": "next build && npx serve out"
   },