nx_heartbeat_monitor.nx

nx_heartbeat_monitor.nx -- WMS-M1: the LIVENESS / HEARTBEAT MONITOR. module: nishi-core.wms.heartbeat_monitor capability: CORE_COMPUTE (durable cross-stream liveness detector built ON WMS-R0) WHAT THIS CLOSES: the autonomous conductor/team-pulse loop can CRASH mid-run and nobody notices -- the work just silently stops. There was no durable detector that could span streams AND survive a crash: nx_progress_watchdog.nx is in-RAM, single-process, monotonic (its STALLED/OK state dies with the process and cannot see a sibling stream). nx_heartbeat_register.nx is capability-registry wiring, not a monitor. M1 reuses ONLY the STALLED/OK semantics of the watchdog; the durable, cross-stream substrate is the WMS-R0 atomic framed-append log (a heartbeat channel). THE MECHANISM: every active workstream BEATS an epoch -- one framed record appended (via the WMS-R0 locked single-write primitive) into a shared heartbeat channel: "HBX ws=<id> epoch=<beatsec> seq=<n> actor=<pid> END" A monitor REPLAYS the channel and, for a set of ws-ids, computes age = now - last_beat and flags STALLED iff (the stream has beaten AND age > threshold). Last-writer-by- MAX-epoch makes it robust to out-of-order append: a fresh beat ALWAYS clears a stale reading (this is what makes the TAMPER/resume lane clear correctly). REUSE / lineage (check-registries-before-building): - fa_append / fa_appendz / fa_cat / fa_catn (nx_framed_append.nx, WMS-R0b): the atomic locked single-write framing primitive -> each beat = exactly one write(). - wsl_at / wsl_field / the per-'\n' line-scan replay skeleton (nx_ws_ledger.nx, WMS-R2): token match + decimal field extract + no-silent-skip flagging. Sovereign: only nx_syscalls + nx_framed_append + nx_ws_ledger. Additive: no organ is modified -- new files only. WRITE DISCIPLINE (the torn-line bug we just killed): EVERY heartbeat record is assembled into ONE buffer (fa_cat/fa_catn) and emitted with a SINGLE fa_append locked write. NEVER a sequence of sys_write() calls. license_tier: ORIGINAL