nx_board_idref_gate.nx

nx_board_idref_gate.nx -- THE COMPARE BOARD'S REFERENTIAL INTEGRITY REFEREE (2026-09-04). WHY THIS EXISTS, AND WHY IT IS A MECHANISM RATHER THAN ANOTHER LAW. On 2026-09-03 a seat appended a rung as LN37 and four log rows as LN36 and BOTH ids were already taken by another lane the same day. It journaled the finding, renumbered to LN41/LN42 after grepping for free ids, and wrote the durable remedy in its own words: "the durable fix is a uniqueness tooth in the compare referee rather than a habit." By 2026-09-04 LN41 AND LN42 had each collided AGAIN -- the renumbering itself landed on ids a third lane had taken while it worked. That is the whole argument for this file: GREP-BEFORE-APPEND IS A HABIT, AND A HABIT LOSES TO CONCURRENCY EVERY TIME. Only something in the path can hold this invariant. WHAT IT JUDGES. A .plan is a board, and a board's ids are its addresses. Three ways an address goes bad: DUPID two rung rows share an id, so the ranker, a watch flip and a done-rule all attach to whichever the reader matches first. Measured live: lang carried one LANDED and one OPEN rung under LN42, which is the dangerous shape -- the board can report the open work as finished. DANGLOG a log row is journaled against a rung id no rung row declares, so the worked plan a crashed session is supposed to inherit points at nothing. DANGMS a milestone lists a member rung that does not exist, so its cumulative estimate is over a set the board cannot enumerate. IT RATCHETS RATHER THAN DEMANDING ZERO, AND THAT IS DELIBERATE. Real offenders already exist that belong to other lanes, and a detector that is permanently RED is one everyone learns to ignore. The bar is knowledge/status/board_idref.baseline; the gate goes RED only when the count RISES, and it TIGHTENS the baseline when the count falls so a fix cannot be undone silently. EVERY OFFENDER IS NAMED IN THE OUTPUT whatever the verdict, because a count without a worklist is not actionable. COMPOSES nx_rowparse_lib for pipe-delimited column extraction rather than hand-rolling a fourth copy of that arithmetic, and gk_* for directory and file access. license_tier: ORIGINAL. Reads the compare trees, writes only its own baseline. No hw writes (Rule 26).