feat: migrate to S3 storage with automatic download and timestamped filenames

- Replace local file storage with S3-compatible object storage

- Add automatic PDF download after generation

- Include timestamps in filenames to ensure uniqueness

- Remove unused static volume from Kubernetes deployment

- Update ConfigMap to remove unused variables and add S3 configuration

- Configure S3 credentials via Kubernetes secrets for both dev and prod environments

- Add boto3 dependency for S3 integration

deploy/base/deployment.yaml

@@ -65,11 +65,3 @@ spec:
         envFrom:
         - configMapRef:
             name: math-exercises-config
-        # Volume mounts for writable directories
-        volumeMounts:
-        - name: static-volume
-          mountPath: /app/app/static
-      # Volumes
-      volumes:
-      - name: static-volume
-        emptyDir: {}