ci: add Renovate configuration for automated dependency updates

Author: krishna-santosh

.github/renovate.json

@@ -0,0 +1,34 @@
+{
+  "extends": ["config:recommended"],
+  "platform": "github",
+  "repositories": ["velopulent/cms"],
+  "onboarding": false,
+  "dependencyDashboard": true,
+  "prConcurrentLimit": 4,
+  "packageRules": [
+    {
+      "description": "Group all Bun dependencies",
+      "matchManagers": ["bun"],
+      "groupName": "Bun dependencies",
+      "separateMajorMinor": false
+    },
+    {
+      "description": "Group all Rust dependencies",
+      "matchManagers": ["cargo"],
+      "groupName": "Rust dependencies",
+      "separateMajorMinor": false
+    },
+    {
+      "description": "Group all GitHub Actions",
+      "matchManagers": ["github-actions"],
+      "groupName": "GitHub Actions",
+      "separateMajorMinor": false
+    },
+    {
+      "description": "Group all Docker dependencies",
+      "matchManagers": ["dockerfile", "docker-compose"],
+      "groupName": "Docker dependencies",
+      "separateMajorMinor": false
+    }
+  ]
+}

.github/workflows/renovate.yml

@@ -0,0 +1,27 @@
+name: Renovate
+
+on:
+  schedule:
+    # 06:30 UTC every Monday.
+    - cron: "30 6 * * 1"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: renovate
+  cancel-in-progress: false
+
+jobs:
+  renovate:
+    name: Update dependencies
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
+      - uses: renovatebot/github-action@22e0a16091fc706b04affe6ae53d5e3358ac4023 # v46.1.19
+        with:
+          configurationFile: .github/renovate.json
+          token: ${{ secrets.RENOVATE_TOKEN }}