p2p: ExchangeServer.handleRangeRequest should assert that from < to

[odeke-em]

go-header/p2p/server.go

Lines 200 to 203 in 18f0eb1

	func (serv *ExchangeServer[H]) handleRangeRequest(ctx context.Context, from, to uint64) ([]H, error) {
	if from == uint64(0) {
	return serv.handleHeadRequest(ctx)
	}

Should also include a check that from < to. Having worked on a bunch of networking, the pain of debugging simple coding errors like a mix up between ranges can be hell and not worth the time, hence insure future selves by simply returning an error when from >= to

Kindly cc-ing @Wondertan

[walldiss]

Hey, thanks for pointing that out!

I totally agree - adding a check to ensure from < to will help prevent any range mix-ups and make the code more robust.