Add Claude Code Stop hook that automatically records session costs when
sessions end. The hook calls `gt costs record` which now can derive the
session name from GT_* environment variables (GT_RIG, GT_POLECAT, GT_CREW,
GT_ROLE).
Changes:
- Add deriveSessionName() to infer tmux session name from environment
- Add Stop hook to settings-autonomous.json and settings-interactive.json
- Add unit tests for deriveSessionName function
When a Gas Town session ends, the Stop hook fires and records the session
cost as a bead event. Costs then appear in `gt costs --today` output.
Closes: gt-ntzhc
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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Updated `gt costs record` to create session.ended events in beads
- Updated `gt costs --today/--week` queries to use bd instead of JSONL
- Removed JSONL ledger support (getLedgerPath, readLedger, WriteLedgerEntry)
- Session costs now stored with event_kind, actor, target, and payload fields
- Filed bd-xwvo for beads bug where --rig flag loses event fields
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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Implements cost tracking v1 for Gas Town agents:
- `gt costs` shows live costs scraped from running tmux sessions
- `gt costs --today/--week` shows historical costs from ledger
- `gt costs --by-role/--by-rig` shows cost breakdowns
- `gt costs record` for Stop hook integration to record final costs
Cost ledger stored at ~/.gt/costs.jsonl with JSONL entries per session.
Ref: gt-nrpiq
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
