Enable solidity optimizer

Contract size was becoming too large without optimization.

hardhat.config.js

@@ -3,7 +3,15 @@ require("hardhat-deploy")
 require("hardhat-deploy-ethers")
 
 module.exports = {
-  solidity: "0.8.4",
+  solidity: {
+    version: "0.8.4",
+    settings: {
+      optimizer: {
+        enabled: true,
+        runs: 1000,
+      },
+    },
+  },
   namedAccounts: {
     deployer: { default: 0 },
   },