nx_netscope_heal.nx

nx_netscope_heal.nx -- NX-NETSCOPE rung 3: goal-directed SELF-HEALING connectivity agent (DECISION CORE). The north-star payload: a device given a goal ("reach nishifamily.com") auto-selects the BEST reachable resolver/path, switches/fails over, and re-verifies -- without flapping. This is the PURE, DETERMINISTIC decision core (no I/O), isolated so it is KAT-able offline (fault-inject a synthetic probe matrix -> assert the chosen resolver + heal action). The live MAPE-K loop (monitor tick, EXECUTE set-resolver, backoff+jitter sleep, circuit breaker) wraps this next increment. Design grounded (research workflow wf_ca778575) in: - Happy Eyeballs v2/v3 (RFC 8305/8306): RACE candidates, pick best -- but "best" = lowest RTT among CORRECT answers (a fast WRONG answer, NXDOMAIN/SERVFAIL/timeout, never wins over a slower correct one). - MAPE-K autonomic loop (monitor->analyze->plan->execute->verify). - Hysteresis / RTT-banding (RFC 2439 RFD spirit): don't switch for a marginal gain -> no flapping. Reuses nxv_cell + ProbeCell + NXNS_* from the shipped probe/verdict layers; composes nx_dns_probe_matrix_parallel results (no new deps). license_tier: ORIGINAL