Add Dex pallet (#407)

* Move pallet-asset-conversion

* update licensing

* initial integration

* Integrate Currency & Assets types

* integrate liquidity tokens

* fmt

* integrate dex pallet tests

* fmt

* compilation error fixes

* integrate dex benchmarks

* fmt

* cargo clippy

* replace all occurrences of "asset" with "coin"

* add the actual add liq/swap logic to in-instructions

* add client side & tests

* fix deny

* Lint and changes

- Renames InInstruction::AddLiquidity to InInstruction::SwapAndAddLiquidity
- Makes create_pool an internal function
- Makes dex-pallet exclusively create pools against a native coin
- Removes various fees
- Adds new crates to GH workflow

* Fix rebase artifacts

* Correct other rebase artifact

* Correct CI specification for liquidity-tokens

* Correct primitives' test to the standardized pallet account scheme

---------

Co-authored-by: Luke Parker <lukeparker5132@gmail.com>

substrate/node/src/chain_spec.rs

@@ -6,8 +6,8 @@ use sc_service::ChainType;
 
 use serai_runtime::{
   primitives::*, WASM_BINARY, opaque::SessionKeys, BABE_GENESIS_EPOCH_CONFIG, RuntimeGenesisConfig,
-  SystemConfig, ValidatorSetsConfig, SessionConfig, BabeConfig, GrandpaConfig,
-  AuthorityDiscoveryConfig, CoinsConfig,
+  SystemConfig, CoinsConfig, DexConfig, ValidatorSetsConfig, SessionConfig, BabeConfig,
+  GrandpaConfig, AuthorityDiscoveryConfig,
 };
 
 pub type ChainSpec = sc_service::GenericChainSpec<RuntimeGenesisConfig>;
@@ -43,6 +43,8 @@ fn testnet_genesis(
         .collect(),
     },
 
+    dex: DexConfig { pools: vec![Coin::Bitcoin, Coin::Ether, Coin::Dai, Coin::Monero] },
+
     validator_sets: ValidatorSetsConfig {
       networks: serai_runtime::primitives::NETWORKS
         .iter()