nx_gauge_lib.nx

nx_gauge_lib.nx -- CE9 (codeeffectiveness sm_gauge_alarm): THE ONE RULER for a GAUGE HEARTBEAT -- written by the beat that measures a gauge, read by the /compare emitter that renders it, and driven in-process by its gate, so the writer and the reader cannot disagree about what STALE, BLIND or ABSENT mean: one classifier, one file shape, one renderer. THE STAMP is the estate's dead-man heartbeat shape -- `ts=<epoch>` FIRST, the way nx_http_probe_lib.hp_write_stamp writes it and nx_cron_watch reads it -- followed by the gauge fields on the same line: ts=<epoch> gauge=<n> axes_known=<k> axes_total=<t> cadence_s=<c> Truncate-written in ONE sys_write: a reader that catches a partial write sees a shorter ts, i.e. an OLDER stamp, which fails in the safe direction. hp_write_stamp is not composed only because it carries ts alone and a gauge needs its axes beside it; the SHAPE is identical so the cron dead-man's switch can watch this file with no change. STATES (ga_state), decided in this order so the most alarming truth wins: ABSENT no readable stamp: nothing has measured, or the writer died before its first beat STALE age > max_age, or age < 0 (a future stamp is clock skew: UNOBSERVABLE, never fresh) BLIND axes_known < axes_total: an axis abstained, and the number beside it acquits nothing FRESH inside max_age with every axis observed max_age is DERIVED from the writer's cadence (GA_MISSED_BEATS beats): one missed beat is tolerated, the second is blindness. ga_render prints the gauge VALUE only when the state is FRESH -- a stale gauge reads STALE on the page and never as zero, which is the rung's accept rule. A stamp whose cadence field is absent judges STALE by construction. license_tier: ORIGINAL No hw writes.