feat(ci): add GitHub Actions workflow for deployment notifications

- Create notify-deployment.yml for deployment notifications
- Filter changes for app and api directories
- Define jobs for frontend and API deployment

Author: MarkusNeusinger

.github/workflows/notify-deployment.yml

@@ -0,0 +1,49 @@
+name: Notify Deployment
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'app/**'
+      - 'api/**'
+      - 'core/**'
+      - 'pyproject.toml'
+
+jobs:
+  changes:
+    runs-on: ubuntu-latest
+    outputs:
+      app: ${{ steps.filter.outputs.app }}
+      api: ${{ steps.filter.outputs.api }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dorny/paths-filter@v3
+        id: filter
+        with:
+          filters: |
+            app:
+              - 'app/**'
+            api:
+              - 'api/**'
+              - 'core/**'
+              - 'pyproject.toml'
+
+  app:
+    needs: changes
+    if: needs.changes.outputs.app == 'true'
+    runs-on: ubuntu-latest
+    environment:
+      name: app
+      url: https://pyplots.ai
+    steps:
+      - run: echo "Frontend deployed via Cloud Build"
+
+  api:
+    needs: changes
+    if: needs.changes.outputs.api == 'true'
+    runs-on: ubuntu-latest
+    environment:
+      name: api
+      url: https://api.pyplots.ai
+    steps:
+      - run: echo "API deployed via Cloud Build"