Restore testnet workflow, config, and deploy script for testnet PR

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: critesjosh

.github/workflows/testnet.yaml

@@ -0,0 +1,41 @@
+name: Testnet Tests
+
+on:
+  push:
+    branches:
+      - testnet
+  pull_request:
+    branches:
+      - testnet
+  workflow_dispatch:
+
+concurrency:
+  group: testnet-deploy
+  cancel-in-progress: true
+
+jobs:
+  testnet-deploy-account:
+    name: Deploy Account to Testnet
+    runs-on: ubuntu-latest
+    env:
+      AZTEC_ENV: testnet
+      L1_PRIVATE_KEY: ${{ secrets.L1_PRIVATE_KEY }}
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v5
+
+      - name: Read Aztec version from config
+        run: echo "AZTEC_VERSION=$(jq -r '.settings.version' config/testnet.json)" >> $GITHUB_ENV
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "24"
+          cache: "yarn"
+
+      - name: Install project dependencies
+        run: yarn
+
+      - name: Deploy account to testnet
+        run: yarn deploy-account::testnet

config/testnet.json

@@ -0,0 +1,18 @@
+{
+  "name": "testnet",
+  "environment": "testnet",
+  "network": {
+    "nodeUrl": "https://rpc.testnet.aztec-labs.com",
+    "l1RpcUrl": "https://ethereum-sepolia-rpc.publicnode.com",
+    "l1ChainId": 11155111
+  },
+  "settings": {
+    "skipLocalNetwork": true,
+    "version": "4.2.0-aztecnr-rc.2"
+  },
+  "timeouts": {
+    "deployTimeout": 1200000,
+    "txTimeout": 180000,
+    "waitTimeout": 60000
+  }
+}

package.json

@@ -15,6 +15,7 @@
     "compile": "aztec compile",
     "deploy": "NODE_NO_WARNINGS=1 node --loader ts-node/esm scripts/deploy_contract.ts",
     "deploy-account": "NODE_NO_WARNINGS=1 node --loader ts-node/esm scripts/deploy_account.ts",
+    "deploy-account::testnet": "NODE_NO_WARNINGS=1 AZTEC_ENV=testnet node --loader ts-node/esm scripts/deploy_account.ts",
     "interaction-existing-contract": "NODE_NO_WARNINGS=1 node --loader ts-node/esm scripts/interaction_existing_contract.ts",
     "multiple-wallet": "NODE_NO_WARNINGS=1 node --loader ts-node/esm scripts/multiple_wallet.ts",
     "get-block": "NODE_NO_WARNINGS=1 node --loader ts-node/esm scripts/get_block.ts",