refactor(contracts): remove deprecated AIPowerRental contract in favor of bounty system

- Delete AIPowerRental.sol (566 lines) - replaced by AgentBounty.sol
- Remove rental agreement system with provider/consumer model
- Remove performance metrics and SLA tracking
- Remove dispute resolution mechanism
- Remove ZK-proof verification for performance
- Remove provider/consumer authorization system
- Bounty system provides superior developer incentive structure

contracts/hardhat.config.js

@@ -0,0 +1,22 @@
+import "@nomicfoundation/hardhat-toolbox";
+import dotenv from "dotenv";
+dotenv.config();
+
+const PRIVATE_KEY = process.env.PRIVATE_KEY || "0x" + "0".repeat(64);
+const INFURA_PROJECT_ID = process.env.INFURA_PROJECT_ID || "";
+
+const config = {
+  solidity: "0.8.20",
+  networks: {
+    hardhat: {},
+    localhost: {
+      url: "http://127.0.0.1:8545"
+    }
+  },
+  paths: {
+    sources: "./contracts",
+    artifacts: "./artifacts"
+  }
+};
+
+export default config;