Godot State Machine Advanced

This covers hierarchical state machines and pushdown automata for Godot, with proper state stacks for interruptions like pause menus, context passing to avoid singleton hell, and transition guards to prevent illegal state changes. The included scripts handle animation syncing, concurrent state orchestration, and resource-driven state definitions. The "never" list is blunt but necessary: propagate physics to child states, always pair enter with exit, and don't push states without a pop plan or you'll leak resources. If you're building layered character behaviors or need states that can pause and resume cleanly, this is the architecture you want.