Replace node-fetch with native undici for HTTP requests throughout pnpm.
Key changes:
- Replace node-fetch with undici's fetch() and dispatcher system
- Replace @pnpm/network.agent with a new dispatcher module in @pnpm/network.fetch
- Cache dispatchers via LRU cache keyed by connection parameters
- Handle proxies via undici ProxyAgent instead of http/https-proxy-agent
- Convert test mocking from nock to undici MockAgent where applicable
- Add minimatch@9 override to fix ESM incompatibility with brace-expansion
Zoltan Kochan