[P2-E6] Consumption reporting (enforcement)

> **Phase resolved: this epic is Phase 3.** The contested label is settled. FR-25 to FR-28 are
> now labelled P3 in the design doc (2026-08-24), which was the condition this epic recorded for
> migrating wholesale into P3-E6's reporting foundation. The FR-28 P2 clause (no sequencing
> capacity without the corresponding burn) stays enforced by construction in Phase 2 via base
> rate 0 plus gated reconciliation, and needs no reporting artifact. With the flat platform fee
> also dropped from MVP, no Phase-2 consumer of a consumption report remains.
>
> **Carried dependency:** FR-3 (gsync-outage settlement) is still P2-labelled in the FR table and
> names this report as its data source. If FR-3 is confirmed P2 and ours, part of this epic gets
> pulled back into Phase 2. Tracked as an open question, not resolved here.
>
> **Component note (carried forward).** The report-*submission* automation (reading the
> sequencer's traffic states, exercising the report choice on cadence) is Sync Operator Node
> functionality, hosted by P2-E5.2's app. Keeping the epic severable is what makes this migration
> a relabel rather than a rewrite.

The burn side of the economy is on-ledger and public; the consumption side happens on a
private synchronizer the SVs cannot see. FR-27 closes the loop: the SO party reports
aggregate consumption (total transactions, average TPS, total traffic consumed) over a
parametrized timeframe, signed on-ledger, reconcilable against settled burn. This is an
enforcement artifact (FR-28 — detectability + governance response), not a reward input;
it also becomes the data source for gsync-outage settlement (FR-3).

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Milestone: Phase 3 · Plan: [P2-E6-consumption-reporting.md](https://github.com/ChainSafe/canton-extending-mainnet/blob/main/docs/planning/phase-2-epics/P2-E6-consumption-reporting.md) · Leaves filed as sub-issues.

Start with docs/planning/phase-2-epics/P2-E6-consumption-reporting.md, then compare its FR-25–FR-28 scope with the FR-3 dependency and the P2-E5.2 component note. Done means the Phase 3 scope is confirmed, the FR-3 question is resolved or tracked explicitly, and the remaining work is divided into actionable sub-issues.

Written by the indexing model from the issue text.