Function render_nonce_stats_json 

pub fn render_nonce_stats_json(count: i64, ttl_seconds: u64) -> Value

nonce count --json and GET /api/nonces.

A count and nothing else: a nonce is a bearer credential until it is consumed, so listing values would put live ones on a screen. The count is the useful part – it should sit near the request rate times the TTL, and a number far above that says the reaper is not running, which is why the TTL travels beside it rather than leaving the reader to go and look it up.