feat: add workflow failure notifications to Discord

Extends the Discord notification system to monitor and report workflow failures in addition to pull requests.

Adds a new workflow_run trigger that listens for completed workflows on the develop branch and sends Discord notifications when any workflow fails.

Separates notification logic into two jobs: one for pull request events and another for workflow failures, each with appropriate conditional guards and using different webhook URLs for distinct notification channels.

Renames the workflow from "Discord Pull Request Notification" to "Discord Notification" to reflect the expanded scope.

.github/workflows/notification.yml

@@ -1,13 +1,18 @@
-name: 🛎️ Discord Pull Request Notification
+name: 🛎️ Discord Notification
 
 on:
   pull_request:
     types: [opened, reopened]
     branches: [develop]
+  workflow_run:
+    workflows: ["*"]
+    types: [completed]
+    branches: [develop]
 
 jobs:
   notify:
     runs-on: ubuntu-24.04
+    if: github.event_name == 'pull_request'
     steps:
       - name: 🛎️ Notify Discord
         uses: Ilshidur/action-discord@d2594079a10f1d6739ee50a2471f0ca57418b554 # 0.4.0
@@ -21,3 +26,21 @@ jobs:
             **By:** ${{ github.event.pull_request.user.login }}
             **Branch:** ${{ github.event.pull_request.head.ref }}
             🔗 ${{ github.event.pull_request.html_url }}
+
+  notify-on-failure:
+    runs-on: ubuntu-24.04
+    if: github.event_name == 'workflow_run' && github.event.workflow_run.conclusion == 'failure'
+    steps:
+      - name: 🚨 Notify Discord on Failure
+        uses: Ilshidur/action-discord@d2594079a10f1d6739ee50a2471f0ca57418b554 # 0.4.0
+        env:
+          DISCORD_WEBHOOK: ${{ secrets.WEBHOOK_FAILED_JOB_URL }}
+          DISCORD_AVATAR: https://avatars.githubusercontent.com/u/193271640
+        with:
+          args: |
+            🚨 **Workflow Failed** in **${{ github.repository }}**
+            **Workflow:** ${{ github.event.workflow_run.name }}
+            **Branch:** ${{ github.event.workflow_run.head_branch }}
+            **Triggered by:** ${{ github.event.workflow_run.triggering_actor.login }}
+            **Commit:** ${{ github.event.workflow_run.head_commit.message }}
+            🔗 ${{ github.event.workflow_run.html_url }}