Provenance

Provenance is built in twice.

• Explicitly: every write through the router adds a line to the venture’s provenance.jsonl, after W3C PROV. The line names the file, the activity (write, draft, accept or baseline), the person or agent and the interface it came through, what the content was derived from, and the decision it acted under.
• Implicitly: git history covers anything written outside the router.

Each line carries the hash of the line before it, so editing, removing or reordering a line breaks the chain, and node schema/check-provenance.mjs fails. A file that changed outside the router since its last line is reported as a warning.

Set MENTURA_ACTOR_ID, MENTURA_MODEL, MENTURA_SESSION and MENTURA_HARNESS so each line names the agent. For a venture that existed before the log, run mentura baseline --venture <id> once.