Remove ethereum-serai/serai-processor-ethereum-contracts

contracts was smashed out of ethereum-serai. Both have now been smashed into
individual crates.

Creates a TODO directory with left-over test code yet to be moved.

processor/ethereum/TODO/tests/crypto.rs

@@ -0,0 +1,29 @@
+use rand_core::OsRng;
+
+use group::ff::{Field, PrimeField};
+use k256::{
+  ecdsa::{
+    self, hazmat::SignPrimitive, signature::hazmat::PrehashVerifier, SigningKey, VerifyingKey,
+  },
+  Scalar, ProjectivePoint,
+};
+
+use frost::{
+  curve::{Ciphersuite, Secp256k1},
+  algorithm::{Hram, IetfSchnorr},
+  tests::{algorithm_machines, sign},
+};
+
+use crate::{crypto::*, tests::key_gen};
+
+// Run the sign test with the EthereumHram
+#[test]
+fn test_signing() {
+  let (keys, _) = key_gen();
+
+  const MESSAGE: &[u8] = b"Hello, World!";
+
+  let algo = IetfSchnorr::<Secp256k1, EthereumHram>::ietf();
+  let _sig =
+    sign(&mut OsRng, &algo, keys.clone(), algorithm_machines(&mut OsRng, &algo, &keys), MESSAGE);
+}