nx_estate_path.nx

nx_estate_path.nx -- THE one act every estate organ performs before reading an artifact: open a knowledge/ path WITHOUT caring which working directory it was launched from. WHY (measured twice in one session, 2026-08-04): 1. nx_swarm_endpoint_lib read "knowledge/swarm_nodes.conf" relative. The gen daemon runs with CWD=/volume1/ai/gen, so the SSOT silently missed and every consumer fell back to stale argv endpoints -- the exact DHCP outage that lib was built to end, reintroduced by a CWD. 2. nx_writebench and nx_writebench_gate each probed only "p" then "../p". Run from buildroot they reported GREEN; run from nishihost (which is the tools-daemon CWD, i.e. EVERY MCP call) the same honest board reported "result=LIAR claimed-artifacts-missing=8". A liar-killer that accuses itself because of a working directory is worse than no liar-killer. ★★★THE LAW: a verdict that changes with the caller's working directory is not a measurement. ★A fix that must be remembered at N sites has to bind to the ONE act all N perform. That act is this function. Callers ask for an estate-relative path; nobody re-spells a probe order again. FAIL-CLOSED: absent everywhere still returns a negative fd. This widens WHERE we look, never what counts as present -- an artifact that does not exist must still read as ABSENT. LAYER: runtime/ (primitive), so both runtime/ and _hdl_build/ organs may import it. Library only: NO main(), so importing it can never cause the double-main trap. license_tier: ORIGINAL module: nishi-core.estate.path capability: ESTATE_PATH_RESOLVE