fix: reset signal pipe handler

[littledivy]

Fixes #28338
Fixes #25258
Fixes #24529
Fixes #15767
Fixes #15045

[0f-0b]

This code currently throws a BrokenPipe error. Would it still be possible to handle the error after this change?

const listener = Deno.listen({ hostname: "::1", port: 0 });
listener.accept();

const conn = await Deno.connect({ hostname: "::1", port: listener.addr.port });
await conn.closeWrite();
await conn.write(new Uint8Array(1));

[littledivy]

Yes, syscall EPIPE errors still work. Only stdio signal pipe errors go away with this change.