chore: sanitise node version (#1026)

.github/workflows/circuits-build.yml

@@ -110,11 +110,23 @@ jobs:
       - name: Add Circom to PATH
         run: echo "$HOME/.cache/circom" >> "$GITHUB_PATH"
 
-      - name: Setup Node.js environment
-        uses: actions/setup-node@v5
+      - name: Read and sanitize Node.js version
+        shell: bash
+        run: |
+          if [ ! -f .nvmrc ] || [ -z "$(cat .nvmrc)" ]; then
+            echo "❌ .nvmrc is missing or empty"; exit 1;
+          fi
+          VERSION="$(tr -d '\r\n' < .nvmrc)"
+          VERSION="${VERSION#v}"
+          if ! [[ "$VERSION" =~ ^[0-9]+(\.[0-9]+){0,2}$ ]]; then
+            echo "Invalid .nvmrc content: '$VERSION'"; exit 1;
+          fi
+          echo "NODE_VERSION=$VERSION" >> "$GITHUB_ENV"
+          echo "NODE_VERSION_SANITIZED=${VERSION//\//-}" >> "$GITHUB_ENV"
+      - name: Use Node.js
+        uses: actions/setup-node@v4
         with:
-          node-version: 22
-          cache: 'yarn'
+          node-version: ${{ env.NODE_VERSION }}
 
       - name: Install Yarn
         run: npm i -g yarn