Feature 4. claude is now launched with --output-format json; the run-log trailing
result JSON is parsed (defensively, never fatal) for usage + total_cost_usd. New
idempotent ALTERs add input_tokens/output_tokens/cache_read_tokens/cost_usd to
agent_runs; the launcher monitor records usage per run, posts a per-agent finish
comment under that agent bot (e.g. Developer gotov · 45.2k in / 12.1k out · $0.21),
and the deployer posts an end-of-task summary (SUM over agent_runs GROUP BY agent)
on done. New src/usage.py holds parse/format/record/summary helpers; test_usage.py
covers parsing a real CLI JSON blob, NULL-on-garbage, recording, formatting, and the
per-task aggregate.
