Implement output.cost_tracking (per-GPU rates, alert / halt thresholds, audit and webhook events) — or retire the promise #924

Deferred work · F-PR29-A2-04 · severity Medium · cost ~1 day · recorded in docs/roadmap/risks-and-decisions.md:94

Summary

The GPU-cost manual (EN + TR) advertises an output.cost_tracking block with per-GPU rates, a currency and alert / halt thresholds, but ForgeConfig has no such field; only the scalar training.gpu_cost_per_hour exists. The PR #29 review deferred it because it needs a CostTrackingConfig model, an audit event when a threshold is crossed and a webhook lifecycle event (which extends the published webhook vocabulary). The documentation issues only correct the pages, so the build-or-drop decision is still open.

Condition or budget

None recorded (the row still names v0.6.x).

State today (re-checked 2026-10-09)

No cost_tracking or CostTrackingConfig exists in forgelm/; the manual labels its examples as forward-looking placeholders.

Related

#428, #241, #429 and #444 correct the cost documentation; none asks for the implementation.

Acceptance criteria

• Either the block exists (schema, audit event, webhook event, EN/TR docs) or the manual and the roadmap drop the promise and the row is closed with that reason.
• The row is removed from the deferral table and the CHANGELOG names its ID (the table's removal contract).

_{Recorded in docs/roadmap/risks-and-decisions.md (read at f94595f) and re-checked against the code on 2026-10-09. The row leaves that table only when the fix is on main, the CHANGELOG names its ID and any promised guard exists.}