feat: Rewrite request ID calculator

[adamspofford-dfinity]

This PR allows request IDs to include nested maps, which necessitated a rewrite of the underlying algorithm. Required for replica-signed queries.

[krpeacock]

This PR removes a lot of comments - are they no longer applicable with the new changes?

[lwshang]

The Request ID example in interface-spec has changed. (Two extra fields)
IMO, we'd better update the corresponding tests: public_spec_example and public_spec_example_api_client.

    #[test]
    fn public_spec_example() {
        #[derive(Serialize)]
        struct PublicSpecExampleStruct {
            request_type: &'static str,
            sender: Principal,
            ingress_expiry: u64,
            canister_id: Principal,
            method_name: &'static str,
            #[serde(with = "serde_bytes")]
            arg: Vec<u8>,
        }
        let data = PublicSpecExampleStruct {
            request_type: "call",
            sender: Principal::anonymous(),
            ingress_expiry: 1685570400000000000u64,
            canister_id: Principal::try_from(&vec![0, 0, 0, 0, 0, 0, 0x04, 0xD2]).unwrap(), // 1234 in u64
            method_name: "hello",
            arg: b"DIDL\x00\xFD*".to_vec(),
        };

        // Hash taken from the example on the public spec.
        let request_id = to_request_id(&data).unwrap();
        assert_eq!(
            hex::encode(request_id.0),
            "1d1091364d6bb8a6c16b203ee75467d59ead468f523eb058880ae8ec80e2b101"
        );
    }

The implementation looks great. And the comments are sufficient.

As Eric suggested, more tests will be great for coverage. The existing test vectors were generated with ic-ref. So it might be more efficient to get some help from ic-ref folks.

[adamspofford-dfinity]

@krpeacock Either no longer applicable, capable of being made more concise by locating the information closer to the code they actually document, or were originally copied verbatim from Serializer's docs and thus pointless.