Function next_registration_nonce 

fn next_registration_nonce() -> u64

Draws the next process-wide registration nonce (≥ 1) for a persistent spawn’s muxbus/registry registrations — see the doc comment at the my_registration_nonce binding in spawn_process for why this is a srv-wide counter rather than the controller-local spawn generation (codex P1 on PR #2500: generations restart per controller instance and can collide across a resync_controller replacement).