feat(scripts): add MACI key generation script

    - Add generateMaciKeys.js script
    - Update package.json with new script command
    - Update .gitignore to exclude maci-keys directory

.gitignore

@@ -154,3 +154,6 @@ packages/cli/contractAddresses.old.json
 packages/circuits/circom/test
 
 **/ts/__benchmarks__/results/**
+
+# MACI keys
+maci-keys/

package.json

@@ -26,7 +26,8 @@
     "test": "lerna run test --ignore maci-integrationtests --ignore maci-cli",
     "types": "lerna run types",
     "docs": "lerna run docs",
-    "prepare": "is-ci || husky"
+    "prepare": "is-ci || husky",
+    "generate-maci-keys": "node scripts/generateMaciKeys.js"
   },
   "author": "PSE",
   "devDependencies": {

scripts/generateMaciKeys.js

@@ -0,0 +1,24 @@
+const { genKeypair } = require('maci-crypto');
+const fs = require('fs');
+const path = require('path');
+
+function generateMaciKeys() {
+  const { privKey, pubKey } = genKeypair();
+
+  const keys = {
+    privateKey: privKey.toString(),
+    publicKey: pubKey.toString()
+  };
+
+  const outputDir = path.join(__dirname, '..', 'maci-keys');
+  if (!fs.existsSync(outputDir)) {
+    fs.mkdirSync(outputDir, { recursive: true });
+  }
+
+  const outputFile = path.join(outputDir, 'maci-keys.json');
+  fs.writeFileSync(outputFile, JSON.stringify(keys, null, 2));
+
+  console.log('MACI keys generated and saved to:', outputFile);
+}
+
+generateMaciKeys();