Tier 3: add CloudFront invalidation

Author: jet432

.github/workflows/deploy.yml

@@ -51,3 +51,9 @@ jobs:
 
       - name: Upload frontend to S3
         run: aws s3 sync Projects/task-tracker/frontend/dist/ s3://${{ secrets.S3_BUCKET }}/ --delete
+
+      - name: Invalidate CloudFront cache
+        run: |
+          aws cloudfront create-invalidation \
+            --distribution-id "${{ secrets.CF_DISTRIBUTION_ID }}" \
+            --paths "/*"