fix(next/font/google): bound Google Fonts fetch timeout on Turbopack (#95981)
### What?
Bound the compile-time Google Fonts fetch on the Turbopack path so `next
dev` / `next build` can't hang forever on a stuck network.
### Why?
`next/font/google` fetches from Google Fonts at compile time. When the
connection *hangs* (captive portal, packet-dropping proxy, broken IPv6),
the fetch had no timeout, so compilation blocked until the OS connect
timeout (~75s) or indefinitely.
### How?
- `FetchClientConfig` gets a `connect_timeout` (10s) and total `timeout`
(60s); Google Fonts overrides them to 5s / 30s.
- Transient failures retry up to 3×, each attempt its own
`duration_span!`.
- On failure: `next build` errors (fails the build), `next dev` warns
and uses the fallback font. Both messages report the attempt count and
suggest `next/font/local`.
### Follow-ups
- [ ] Reduce the dev-mode timeout (build keeps the longer value).
- [ ] Port the fix to the webpack/JS path (`packages/font/src/google`).
Related: #92301. #76473.
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Co-authored-by: Benjamin Woodruff <benjamin.woodruff@vercel.com>