Adds .claude/helpers/foxhunt-audit-router.sh that suggests foxhunt-* auditor
agents based on edited file path. Warn-only, <200ms, never blocks. Dedup
state file .claude/.foxhunt-audit-state cleared at SessionStart by sibling
script. Settings.json additive merge — existing hooks preserved.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>