Design notes

How a subsystem is built and which normative reference it answers to. For maintainers; the behavior a user sees is the guide.

• The action executor — how a token moves through a lowered ActionGraph
• Orthogonal regions — concurrent substates, an OpenSysML extension against UML 2.5.1 semantics
• Pseudostates — choice, junction, fork, join, entry/exit points and history
• Python gRPC bindings — the service and client design
• Visual modeling in VS Code — the live diagram panel, the diagram-driven edits, and the graphical editor it builds to

The staged plans that built the bindings, kept for their rationale: phase 1 (the service), phase 2 (the client), phase 3 and its fixes, phase 4.