feat: legacy cow amm safe indexer (#81)

## Description

This PR adds a rust utility that indexes all legacy CoW AMMs that have
been created using the Safe module, to be used for statically populating
the `ConstantProductHelper.sol` contract in a forthcoming PR.

## Testing

1. Ensure you have a running `rust` environment (the devcontainer has
been updated to include one).
2. Change into the `utils` directory and: `RPC_URL=cargo run --bin
cow-amm-indexer`

**NOTE**: As this indexer looks back over previous blocks, the RPC being
used must have `receipts` available for the respective contracts that
are being analysed. For example, if you want to test this for mainnet,
`https://eth.merkle.io` is suitable.

---------

Co-authored-by: Federico Giacon <[email protected]>

.devcontainer/devcontainer.json

@@ -1,14 +1,20 @@
 {
-	"name": "Foundry",
-	"image": "mcr.microsoft.com/devcontainers/base:0",
-	"features": {
-		"ghcr.io/nlordell/features/foundry": {},
-	},
-	"customizations": {
-		"vscode": {
-			"extensions": [
-				"JuanBlanco.solidity"
-			]
-		}
-	}
+    "name": "Foundry + Rust Development Container",
+    "image": "mcr.microsoft.com/devcontainers/base:debian",
+    "features": {
+        "ghcr.io/devcontainers/features/rust:1": {
+            "version": "nightly-2024-06-07"
+        },
+       "ghcr.io/nlordell/features/foundry": {}
+    },
+    "postCreateCommand": "sudo DEBIAN_FRONTEND=noninteractive apt-get update && sudo DEBIAN_FRONTEND=noninteractive apt-get install -y pkg-config libssl-dev",
+    "customizations": {
+        "vscode": {
+            "extensions": [
+                "rust-lang.rust-analyzer",
+                "JuanBlanco.solidity"
+            ]
+        }
+    }
 }
+

.gitignore

@@ -9,3 +9,6 @@ out/
 
 # Dotenv file
 .env
+
+# Rust
+/utils/target