feat: Initial workflow engine stub

Author: Alan Christie

.pre-commit-config.yaml

@@ -74,4 +74,5 @@ repos:
     - jinja2==3.0.3
     - jsonschema >= 3.2.0, < 4.0
     - pyyaml >= 5.3.1, < 7.0
+    - im-protobuf >= 7.0.0
     files: ^workflow/.*\.py$