build: Improve the backend Makefile

.gitignore

@@ -1,3 +1,12 @@
+# Global ignores
 **/node_modules/
 **/.cache/
 **/dist/
+
+# Backend ignores
+backend/backend.tar
+backend/backend.tgz
+
+# Server ignores
+server/*.pem
+server/db/