field-audit: read the results, then close what is finished

Before you use this skill, check that HERDR_ENV=1. If it is not 1, tell the user that you do not run inside a herdr pane. Then stop.

A closed pane destroys unread output, so this skill reads first and closes last. field-agent dispatches one field agent, field-handler runs a room, herdr carries the semantics herdr --skill leaves out; the four are one suite.

The ledger tool field.py lives in the field-agent skill's directory (one copy, so it cannot go stale). Find it once and call it <agent_dir>:

find ~/.claude ~/.agents -maxdepth 5 -type d -path '*skills/field-agent' 2>/dev/null