v0.3.0 — Petri Net FSM, SNN Bridge, Event-Driven Transitions

Added

• Petri net regime FSM — PetriNet, PetriNetAdapter, ProtocolNetSpec for multi-phase protocol sequencing
• Event-driven transitions — EventBus + RegimeEvent pub/sub with bounded history
• RegimeManager.force_transition() — bypasses cooldown and hysteresis hold
• hysteresis_hold_steps — consecutive-step requirement for soft downward transitions
• SNN controller bridge (SNNControllerBridge) — pure-numpy LIF rate model + Nengo/Lava optional backends
• Rust RegimeManager.force_transition() and transition_log for FFI parity
• ~90 new tests across 5 new test files

Changed

• SupervisorPolicy accepts optional petri_adapter argument
• BoundaryObserver.observe() accepts optional step kwarg
• RegimeManager constructor accepts event_bus and hysteresis_hold_steps params

See CHANGELOG.md for full details.