LICITRA-SENTRY v0.2: Execution Ticket System, Mandatory Mediation, and Witnessed Transparency for Agentic AI Authorization

Technical report documenting LICITRA-SENTRY v0.2, which adds execution tickets (Ed25519-signed), a tool proxy gateway with replay protection, and a CT-style witnessed transparency layer to the five-gate Chain of Intent authorization pipeline for agentic AI systems. 13 reproducible experiments (E01-E13) demonstrate: authorized flow, proxy bypass rejection, replay attack detection, payload modification detection, delegation escalation blocking, PII exfiltration blocking, audit chain integrity, epoch witnessing, operator rewrite detection, external auditor verification, tampered receipt rejection, and chain break detection. Without witnesses, tamper-evidence requires operator honesty. With witnesses, tamper-evidence holds even under operator compromise unless all witnesses collude. Open-source reference implementation under MIT license.