chore: add notification action

[skip ci]

.github/actions/notify/action.yaml

@@ -1,8 +1,11 @@
-name: Send pull request notification to Google Chat
-description: |
-  Sends a notification to a Google Chat room when a pull request is opened.
+name: Send notification via Google Chat
+description: "Sends a notification to a Google Chat room when a pull request is opened."
 
 inputs:
+  webhook_url:
+    description: "The URL of the Google Chat webhook."
+    required: true
+
   title:
     description: "The title of the notification."
     required: true
@@ -32,28 +35,35 @@ inputs:
     required: true
     default: 'none'
 
-
 runs:
   using: "composite"
   steps:
     - name: Install prerequisites
       shell: bash
-      run: apt update && apt install -y curl jq
+      run: |
+        echo "::group::apt install"
+        set -e
+        apt update
+        apt install -y curl jq
+        echo "::endgroup::"
 
-    - name: Send PR notification to Google Chat
+    - name: Notify via Google Chat Webhook
       shell: bash
+      env:
+        WEBHOOK: ${{ inputs.webhook_url }}
       run: |
         set -e
 
         PAYLOAD=$(jq -n \
-          --arg repo "${{ github.repository }}" \
-          --arg title "${{ inputs.event_title }}" \
-          --arg body "${{ inputs.event_body }}" \
-          --arg author "${{ inputs.event_author }}" \
-          --arg url "${{ inputs.event_url }}" \
+          --arg header_title "${{ inputs.title }}" \
+          --arg repo "${{ github.repository || '' }}" \
+          --arg title "${{ inputs.event_title || 'no event title given' }}" \
+          --arg body "${{ inputs.event_body || 'no event body given' }}" \
+          --arg author "${{ inputs.event_author || 'no event author given' }}" \
+          --arg url "${{ inputs.event_url || 'no event url given' }}" \
           '{
             "header": {
-              "title": "${{ inputs.title }}",
+              "title": "$header_title",
               "subtitle": "Repo: \($repo)",
               "imageUrl": "https://cdn.jsdelivr.net/gh/homarr-labs/dashboard-icons/png/git.png",
               "imageType": "SQUARE"
@@ -101,6 +111,9 @@ runs:
             ]
           }')
 
-        curl --fail-with-body -X POST -H 'Content-Type: application/json' \
-          "${{ secrets.GOOGLE_WEBHOOK_URL }}&messageReplyOption=REPLY_MESSAGE_FALLBACK_TO_NEW_THREAD&threadKey=${REPO}/pr/${PR_NUMBER}" \
+        curl \
+          --fail-with-body \
+          -X POST \
+          -H 'Content-Type: application/json' \
+          "${{ inputs.webhook_url }}&messageReplyOption=REPLY_MESSAGE_FALLBACK_TO_NEW_THREAD&threadKey=${{ github.repository }}/pr/${{ inputs.event_number }}" \
           -d "$(jq -n --argjson card "$PAYLOAD" '{ "cardsV2": [ { "cardId": "new-pr", "card": $card } ] }')"