feat(renovate): add renovate config validator shared action

.release-please-manifest.json

@@ -23,5 +23,6 @@
     "actions/get-latest-workflow-artifact": "0.2.0",
     "actions/create-github-app-token": "0.2.0",
     "actions/run-capslock": "0.2.0",
-    "actions/azure-trusted-signing": "1.0.0"
+    "actions/azure-trusted-signing": "1.0.0",
+    "actions/validate-renovate-config": "0.1.0"
 }

actions/validate-renovate-config/README.md

@@ -0,0 +1,50 @@
+# validate-renovate-config
+
+Validates Renovate configuration files using [renovate-config-validator](https://docs.renovatebot.com/config-validation/).
+
+## Inputs
+
+- `path`: Path to the Renovate config file to validate. Defaults to `renovate.json`.
+
+## Example workflow
+
+```yaml
+name: Validate Renovate Config
+
+on:
+  pull_request:
+    paths:
+      - 'renovate.json'
+  push:
+    branches:
+      - main
+    paths:
+      - 'renovate.json'
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+      - name: Validate Renovate Config
+        uses: grafana/shared-workflows/actions/validate-renovate-config@validate-renovate-config/v1.0.0
+```
+
+## Validating multiple files
+
+To validate multiple config files, call the action multiple times:
+
+```yaml
+- name: Validate main config
+  uses: grafana/shared-workflows/actions/validate-renovate-config@validate-renovate-config/v1.0.0
+  with:
+    path: renovate.json
+
+- name: Validate preset
+  uses: grafana/shared-workflows/actions/validate-renovate-config@validate-renovate-config/v1.0.0
+  with:
+    path: presets/default.json
+```

actions/validate-renovate-config/action.yml

@@ -0,0 +1,20 @@
+name: Validate Renovate Config
+description: Validates Renovate configuration files using renovate-config-validator
+
+inputs:
+  path:
+    description: Path to the Renovate config file to validate (e.g., 'renovate.json')
+    required: false
+    default: renovate.json
+
+runs:
+  using: composite
+  steps:
+    - name: Setup Node.js
+      uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
+      with:
+        node-version: '20'
+
+    - name: Validate Renovate config
+      shell: bash
+      run: npx --yes --package renovate -- renovate-config-validator "${{ inputs.path }}"

release-please-config.json

@@ -154,6 +154,11 @@
     "actions/create-github-app-token": {
       "package-name": "create-github-app-token",
       "extra-files": ["README.md"]
+    },
+    "actions/validate-renovate-config": {
+      "package-name": "validate-renovate-config",
+      "extra-files": ["README.md"],
+      "initial-version": "0.1.0"
     }
   },
   "release-type": "simple",