Update dependencies and add audit workflow (#114)

.github/workflows/audit.yml

@@ -0,0 +1,25 @@
+name: Run Cargo audit
+
+on:
+  push:
+    branches:
+      - 'main'
+  schedule:
+    - cron: '0 0 * * 1' # Run on Mondays
+  workflow_dispatch:
+
+jobs:
+  audit:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Install dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y protobuf-compiler
+
+      - name: Audit dependencies
+        run: cargo audit