Agent Skills: falsify

Adversarial falsification of sigint research findings. Generates disconfirming queries, executes web-only adversarial search, assigns ordinal verdicts (falsified | weakened | survived | inconclusive), and applies remediation (quarantine, confidence downgrade, follow-up queue). Invocable standalone via `/sigint:falsify` or as Phase 3.6 gate inside the research-orchestrator before report finalization. Use when the user invokes /sigint:falsify.