nx_doctor_apply.nx

nx_doctor_apply.nx -- THE NISHI DOCTOR's "graceful apply WITHOUT competition" core rung. Operator: route a fix through the Doctor so it is applied gracefully without racing a workstream that is concurrently editing the same shared organ. Synthesized from the Nishi Researcher's S-class corpus (knowledge/fetched/doc_*.raw): LOCK (mutual exclusion, axis A: nx_arbiter fl_acquire) + EXACT-CONTEXT-MATCH apply (axes B optimistic/CAS + C 3-way-merge/patch context: apply ONLY where the target region still matches the CURRENT file exactly-once -> a concurrent edit that touched my region makes the match FAIL = REFUSE, never clobber; an edit elsewhere leaves the match intact = apply = a clean merge for non-overlapping edits) + ATOMIC tmp+rename (axis F: no torn write). Fail-closed: any ambiguity (no match / multi-match) -> REFUSE. This does NOT verify or admit its own work (RACI: the Engineer re-verifies, the Warden admits) -- it is the safe APPLY primitive the Doctor's fix queue (next rung) drives one-at-a-time. usage: nx_doctor_apply <target> <oldstr-file> <newstr-file> [requester] reads oldstr/newstr from files so multi-line patches work (NUL-free byte spans). license_tier: ORIGINAL