Cure FSM API Wrapper

This module provides the Cure-level FSM API that matches the design in lib/std/fsm.cure. It wraps the underlying cure_fsm_runtime gen_server to provide:

• start_fsm/1: Start an FSM instance from a module
• fsm_cast/2: Send events asynchronously
• fsm_advertise/2: Register a name for an FSM
• fsm_state/1: Query current state and payload

The FSM definitions in Cure modules are compiled to:

1. A record type for the payload
2. A list of transitions with handler functions
3. An initial state and initial payload

This module bridges the gap between Cure's high-level FSM syntax and the Erlang gen_server runtime.